diff --git a/electron/ipc/system.ts b/electron/ipc/system.ts
index cc701a4..e1fe385 100644
--- a/electron/ipc/system.ts
+++ b/electron/ipc/system.ts
@@ -39,6 +39,13 @@ import {
   getWindowIconPath,
   updateCloseToTraySetting
 } from '../window/create-window';
+import {
+  deleteSavedTheme,
+  getSavedThemesPath,
+  listSavedThemes,
+  readSavedTheme,
+  writeSavedTheme
+} from '../theme-library';
 
 const DEFAULT_MIME_TYPE = 'application/octet-stream';
 const FILE_CLIPBOARD_FORMATS = [
@@ -325,6 +332,15 @@ export function setupSystemHandlers(): void {
   });
 
   ipcMain.handle('get-app-data-path', () => app.getPath('userData'));
+  ipcMain.handle('get-saved-themes-path', async () => await getSavedThemesPath());
+  ipcMain.handle('list-saved-themes', async () => await listSavedThemes());
+  ipcMain.handle('read-saved-theme', async (_event, fileName: string) => await readSavedTheme(fileName));
+  ipcMain.handle('write-saved-theme', async (_event, fileName: string, text: string) => {
+    return await writeSavedTheme(fileName, text);
+  });
+  ipcMain.handle('delete-saved-theme', async (_event, fileName: string) => {
+    return await deleteSavedTheme(fileName);
+  });
 
   ipcMain.handle('get-desktop-settings', () => getDesktopSettingsSnapshot());
 
diff --git a/electron/preload.ts b/electron/preload.ts
index f956dbe..29daf80 100644
--- a/electron/preload.ts
+++ b/electron/preload.ts
@@ -102,6 +102,12 @@ export interface WindowStateSnapshot {
   isMinimized: boolean;
 }
 
+export interface SavedThemeFileDescriptor {
+  fileName: string;
+  modifiedAt: number;
+  path: string;
+}
+
 function readLinuxDisplayServer(): string {
   if (process.platform !== 'linux') {
     return 'N/A';
@@ -134,6 +140,11 @@ export interface ElectronAPI {
   onLinuxScreenShareMonitorAudioChunk: (listener: (payload: LinuxScreenShareMonitorAudioChunkPayload) => void) => () => void;
   onLinuxScreenShareMonitorAudioEnded: (listener: (payload: LinuxScreenShareMonitorAudioEndedPayload) => void) => () => void;
   getAppDataPath: () => Promise<string>;
+  getSavedThemesPath: () => Promise<string>;
+  listSavedThemes: () => Promise<SavedThemeFileDescriptor[]>;
+  readSavedTheme: (fileName: string) => Promise<string>;
+  writeSavedTheme: (fileName: string, text: string) => Promise<boolean>;
+  deleteSavedTheme: (fileName: string) => Promise<boolean>;
   consumePendingDeepLink: () => Promise<string | null>;
   getDesktopSettings: () => Promise<{
     autoUpdateMode: 'auto' | 'off' | 'version';
@@ -230,6 +241,11 @@ const electronAPI: ElectronAPI = {
     };
   },
   getAppDataPath: () => ipcRenderer.invoke('get-app-data-path'),
+  getSavedThemesPath: () => ipcRenderer.invoke('get-saved-themes-path'),
+  listSavedThemes: () => ipcRenderer.invoke('list-saved-themes'),
+  readSavedTheme: (fileName) => ipcRenderer.invoke('read-saved-theme', fileName),
+  writeSavedTheme: (fileName, text) => ipcRenderer.invoke('write-saved-theme', fileName, text),
+  deleteSavedTheme: (fileName) => ipcRenderer.invoke('delete-saved-theme', fileName),
   consumePendingDeepLink: () => ipcRenderer.invoke('consume-pending-deep-link'),
   getDesktopSettings: () => ipcRenderer.invoke('get-desktop-settings'),
   showDesktopNotification: (payload) => ipcRenderer.invoke('show-desktop-notification', payload),
diff --git a/electron/theme-library.ts b/electron/theme-library.ts
new file mode 100644
index 0000000..da1c180
--- /dev/null
+++ b/electron/theme-library.ts
@@ -0,0 +1,92 @@
+import { app } from 'electron';
+import * as fsp from 'fs/promises';
+import * as path from 'path';
+
+export interface SavedThemeFileDescriptor {
+  fileName: string;
+  modifiedAt: number;
+  path: string;
+}
+
+const SAVED_THEME_FILE_NAME_PATTERN = /^[A-Za-z0-9][A-Za-z0-9._-]*\.json$/;
+
+function resolveSavedThemesPath(): string {
+  return path.join(app.getPath('userData'), 'themes');
+}
+
+async function ensureSavedThemesPath(): Promise<string> {
+  const themesPath = resolveSavedThemesPath();
+
+  await fsp.mkdir(themesPath, { recursive: true });
+
+  return themesPath;
+}
+
+function assertSavedThemeFileName(fileName: string): string {
+  const normalized = typeof fileName === 'string'
+    ? fileName.trim()
+    : '';
+
+  if (!SAVED_THEME_FILE_NAME_PATTERN.test(normalized) || normalized.includes('..')) {
+    throw new Error('Invalid saved theme file name.');
+  }
+
+  return normalized;
+}
+
+async function resolveSavedThemeFilePath(fileName: string): Promise<string> {
+  const themesPath = await ensureSavedThemesPath();
+
+  return path.join(themesPath, assertSavedThemeFileName(fileName));
+}
+
+export async function getSavedThemesPath(): Promise<string> {
+  return await ensureSavedThemesPath();
+}
+
+export async function listSavedThemes(): Promise<SavedThemeFileDescriptor[]> {
+  const themesPath = await ensureSavedThemesPath();
+  const entries = await fsp.readdir(themesPath, { withFileTypes: true });
+  const files = entries.filter((entry) => entry.isFile() && entry.name.toLowerCase().endsWith('.json'));
+
+  const descriptors = await Promise.all(files.map(async (entry) => {
+    const filePath = path.join(themesPath, entry.name);
+    const stats = await fsp.stat(filePath);
+
+    return {
+      fileName: entry.name,
+      modifiedAt: Math.round(stats.mtimeMs),
+      path: filePath
+    } satisfies SavedThemeFileDescriptor;
+  }));
+
+  return descriptors.sort((left, right) => right.modifiedAt - left.modifiedAt || left.fileName.localeCompare(right.fileName));
+}
+
+export async function readSavedTheme(fileName: string): Promise<string> {
+  const filePath = await resolveSavedThemeFilePath(fileName);
+
+  return await fsp.readFile(filePath, 'utf8');
+}
+
+export async function writeSavedTheme(fileName: string, text: string): Promise<boolean> {
+  const filePath = await resolveSavedThemeFilePath(fileName);
+
+  await fsp.writeFile(filePath, text, 'utf8');
+  return true;
+}
+
+export async function deleteSavedTheme(fileName: string): Promise<boolean> {
+  const filePath = await resolveSavedThemeFilePath(fileName);
+
+  try {
+    await fsp.unlink(filePath);
+    return true;
+  } catch (error) {
+    if ((error as { code?: string }).code === 'ENOENT') {
+      return true;
+    }
+
+    throw error;
+  }
+}
\ No newline at end of file
diff --git a/package-lock.json b/package-lock.json
index ac94883..4966a71 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -14,6 +14,12 @@
         "@angular/forms": "^21.0.0",
         "@angular/platform-browser": "^21.0.0",
         "@angular/router": "^21.0.0",
+        "@codemirror/commands": "^6.10.3",
+        "@codemirror/lang-json": "^6.0.2",
+        "@codemirror/language": "^6.12.3",
+        "@codemirror/state": "^6.6.0",
+        "@codemirror/theme-one-dark": "^6.1.3",
+        "@codemirror/view": "^6.41.0",
         "@ng-icons/core": "^33.0.0",
         "@ng-icons/lucide": "^33.0.0",
         "@ngrx/effects": "^21.0.1",
@@ -27,6 +33,7 @@
         "auto-launch": "^5.0.6",
         "class-variance-authority": "^0.7.1",
         "clsx": "^2.1.1",
+        "codemirror": "^6.0.2",
         "cytoscape": "^3.33.1",
         "electron-updater": "^6.6.2",
         "mermaid": "^11.12.3",
@@ -2697,6 +2704,109 @@
       "integrity": "sha512-4mudFAQ6H+MqBTfqLmU7G1ZwRzCLfJEooL/fsF6rCX5eePMbGhoy5n4g+G4vlh2muDcsCTJtL+uKbOzWxs5LHA==",
       "license": "Apache-2.0"
     },
+    "node_modules/@codemirror/autocomplete": {
+      "version": "6.20.1",
+      "resolved": "https://registry.npmjs.org/@codemirror/autocomplete/-/autocomplete-6.20.1.tgz",
+      "integrity": "sha512-1cvg3Vz1dSSToCNlJfRA2WSI4ht3K+WplO0UMOgmUYPivCyy2oueZY6Lx7M9wThm7SDUBViRmuT+OG/i8+ON9A==",
+      "license": "MIT",
+      "dependencies": {
+        "@codemirror/language": "^6.0.0",
+        "@codemirror/state": "^6.0.0",
+        "@codemirror/view": "^6.17.0",
+        "@lezer/common": "^1.0.0"
+      }
+    },
+    "node_modules/@codemirror/commands": {
+      "version": "6.10.3",
+      "resolved": "https://registry.npmjs.org/@codemirror/commands/-/commands-6.10.3.tgz",
+      "integrity": "sha512-JFRiqhKu+bvSkDLI+rUhJwSxQxYb759W5GBezE8Uc8mHLqC9aV/9aTC7yJSqCtB3F00pylrLCwnyS91Ap5ej4Q==",
+      "license": "MIT",
+      "dependencies": {
+        "@codemirror/language": "^6.0.0",
+        "@codemirror/state": "^6.6.0",
+        "@codemirror/view": "^6.27.0",
+        "@lezer/common": "^1.1.0"
+      }
+    },
+    "node_modules/@codemirror/lang-json": {
+      "version": "6.0.2",
+      "resolved": "https://registry.npmjs.org/@codemirror/lang-json/-/lang-json-6.0.2.tgz",
+      "integrity": "sha512-x2OtO+AvwEHrEwR0FyyPtfDUiloG3rnVTSZV1W8UteaLL8/MajQd8DpvUb2YVzC+/T18aSDv0H9mu+xw0EStoQ==",
+      "license": "MIT",
+      "dependencies": {
+        "@codemirror/language": "^6.0.0",
+        "@lezer/json": "^1.0.0"
+      }
+    },
+    "node_modules/@codemirror/language": {
+      "version": "6.12.3",
+      "resolved": "https://registry.npmjs.org/@codemirror/language/-/language-6.12.3.tgz",
+      "integrity": "sha512-QwCZW6Tt1siP37Jet9Tb02Zs81TQt6qQrZR2H+eGMcFsL1zMrk2/b9CLC7/9ieP1fjIUMgviLWMmgiHoJrj+ZA==",
+      "license": "MIT",
+      "dependencies": {
+        "@codemirror/state": "^6.0.0",
+        "@codemirror/view": "^6.23.0",
+        "@lezer/common": "^1.5.0",
+        "@lezer/highlight": "^1.0.0",
+        "@lezer/lr": "^1.0.0",
+        "style-mod": "^4.0.0"
+      }
+    },
+    "node_modules/@codemirror/lint": {
+      "version": "6.9.5",
+      "resolved": "https://registry.npmjs.org/@codemirror/lint/-/lint-6.9.5.tgz",
+      "integrity": "sha512-GElsbU9G7QT9xXhpUg1zWGmftA/7jamh+7+ydKRuT0ORpWS3wOSP0yT1FOlIZa7mIJjpVPipErsyvVqB9cfTFA==",
+      "license": "MIT",
+      "dependencies": {
+        "@codemirror/state": "^6.0.0",
+        "@codemirror/view": "^6.35.0",
+        "crelt": "^1.0.5"
+      }
+    },
+    "node_modules/@codemirror/search": {
+      "version": "6.6.0",
+      "resolved": "https://registry.npmjs.org/@codemirror/search/-/search-6.6.0.tgz",
+      "integrity": "sha512-koFuNXcDvyyotWcgOnZGmY7LZqEOXZaaxD/j6n18TCLx2/9HieZJ5H6hs1g8FiRxBD0DNfs0nXn17g872RmYdw==",
+      "license": "MIT",
+      "dependencies": {
+        "@codemirror/state": "^6.0.0",
+        "@codemirror/view": "^6.37.0",
+        "crelt": "^1.0.5"
+      }
+    },
+    "node_modules/@codemirror/state": {
+      "version": "6.6.0",
+      "resolved": "https://registry.npmjs.org/@codemirror/state/-/state-6.6.0.tgz",
+      "integrity": "sha512-4nbvra5R5EtiCzr9BTHiTLc+MLXK2QGiAVYMyi8PkQd3SR+6ixar/Q/01Fa21TBIDOZXgeWV4WppsQolSreAPQ==",
+      "license": "MIT",
+      "dependencies": {
+        "@marijn/find-cluster-break": "^1.0.0"
+      }
+    },
+    "node_modules/@codemirror/theme-one-dark": {
+      "version": "6.1.3",
+      "resolved": "https://registry.npmjs.org/@codemirror/theme-one-dark/-/theme-one-dark-6.1.3.tgz",
+      "integrity": "sha512-NzBdIvEJmx6fjeremiGp3t/okrLPYT0d9orIc7AFun8oZcRk58aejkqhv6spnz4MLAevrKNPMQYXEWMg4s+sKA==",
+      "license": "MIT",
+      "dependencies": {
+        "@codemirror/language": "^6.0.0",
+        "@codemirror/state": "^6.0.0",
+        "@codemirror/view": "^6.0.0",
+        "@lezer/highlight": "^1.0.0"
+      }
+    },
+    "node_modules/@codemirror/view": {
+      "version": "6.41.0",
+      "resolved": "https://registry.npmjs.org/@codemirror/view/-/view-6.41.0.tgz",
+      "integrity": "sha512-6H/qadXsVuDY219Yljhohglve8xf4B8xJkVOEWfA5uiYKiTFppjqsvsfR5iPA0RbvRBoOyTZpbLIxe9+0UR8xA==",
+      "license": "MIT",
+      "dependencies": {
+        "@codemirror/state": "^6.6.0",
+        "crelt": "^1.0.6",
+        "style-mod": "^4.1.0",
+        "w3c-keyname": "^2.2.4"
+      }
+    },
     "node_modules/@develar/schema-utils": {
       "version": "2.6.5",
       "resolved": "https://registry.npmjs.org/@develar/schema-utils/-/schema-utils-2.6.5.tgz",
@@ -5672,6 +5782,41 @@
       "integrity": "sha512-Vo+PSpZG2/fmgmiNzYK9qWRh8h/CHrwD0mo1h1DzL4yzHNSfWYujGTYsWGreD000gcgmZ7K4Ys6Tx9TxtsKdDw==",
       "license": "MIT"
     },
+    "node_modules/@lezer/common": {
+      "version": "1.5.1",
+      "resolved": "https://registry.npmjs.org/@lezer/common/-/common-1.5.1.tgz",
+      "integrity": "sha512-6YRVG9vBkaY7p1IVxL4s44n5nUnaNnGM2/AckNgYOnxTG2kWh1vR8BMxPseWPjRNpb5VtXnMpeYAEAADoRV1Iw==",
+      "license": "MIT"
+    },
+    "node_modules/@lezer/highlight": {
+      "version": "1.2.3",
+      "resolved": "https://registry.npmjs.org/@lezer/highlight/-/highlight-1.2.3.tgz",
+      "integrity": "sha512-qXdH7UqTvGfdVBINrgKhDsVTJTxactNNxLk7+UMwZhU13lMHaOBlJe9Vqp907ya56Y3+ed2tlqzys7jDkTmW0g==",
+      "license": "MIT",
+      "dependencies": {
+        "@lezer/common": "^1.3.0"
+      }
+    },
+    "node_modules/@lezer/json": {
+      "version": "1.0.3",
+      "resolved": "https://registry.npmjs.org/@lezer/json/-/json-1.0.3.tgz",
+      "integrity": "sha512-BP9KzdF9Y35PDpv04r0VeSTKDeox5vVr3efE7eBbx3r4s3oNLfunchejZhjArmeieBH+nVOpgIiBJpEAv8ilqQ==",
+      "license": "MIT",
+      "dependencies": {
+        "@lezer/common": "^1.2.0",
+        "@lezer/highlight": "^1.0.0",
+        "@lezer/lr": "^1.0.0"
+      }
+    },
+    "node_modules/@lezer/lr": {
+      "version": "1.4.8",
+      "resolved": "https://registry.npmjs.org/@lezer/lr/-/lr-1.4.8.tgz",
+      "integrity": "sha512-bPWa0Pgx69ylNlMlPvBPryqeLYQjyJjqPx+Aupm5zydLIF3NE+6MMLT8Yi23Bd9cif9VS00aUebn+6fDIGBcDA==",
+      "license": "MIT",
+      "dependencies": {
+        "@lezer/common": "^1.0.0"
+      }
+    },
     "node_modules/@listr2/prompt-adapter-inquirer": {
       "version": "3.0.5",
       "resolved": "https://registry.npmjs.org/@listr2/prompt-adapter-inquirer/-/prompt-adapter-inquirer-3.0.5.tgz",
@@ -5865,6 +6010,12 @@
         "node": ">= 10.0.0"
       }
     },
+    "node_modules/@marijn/find-cluster-break": {
+      "version": "1.0.2",
+      "resolved": "https://registry.npmjs.org/@marijn/find-cluster-break/-/find-cluster-break-1.0.2.tgz",
+      "integrity": "sha512-l0h88YhZFyKdXIFNfSWpyjStDjGHwZ/U7iobcK1cQQD8sejsONdQtTVU+1wVN1PBw40PiiHB1vA5S7VTfQiP9g==",
+      "license": "MIT"
+    },
     "node_modules/@mermaid-js/parser": {
       "version": "1.0.0",
       "resolved": "https://registry.npmjs.org/@mermaid-js/parser/-/parser-1.0.0.tgz",
@@ -14138,6 +14289,21 @@
       "integrity": "sha512-Oofo0pq3IKnsFtuHqSF7TqBfr71aeyZDVJ0HpmqB7FBM2qEigL0iPONSCZSO9pE9dZTAxANe5XHG9Uy0YMv8cg==",
       "license": "MIT"
     },
+    "node_modules/codemirror": {
+      "version": "6.0.2",
+      "resolved": "https://registry.npmjs.org/codemirror/-/codemirror-6.0.2.tgz",
+      "integrity": "sha512-VhydHotNW5w1UGK0Qj96BwSk/Zqbp9WbnyK2W/eVMv4QyF41INRGpjUhFJY7/uDNuudSc33a/PKr4iDqRduvHw==",
+      "license": "MIT",
+      "dependencies": {
+        "@codemirror/autocomplete": "^6.0.0",
+        "@codemirror/commands": "^6.0.0",
+        "@codemirror/language": "^6.0.0",
+        "@codemirror/lint": "^6.0.0",
+        "@codemirror/search": "^6.0.0",
+        "@codemirror/state": "^6.0.0",
+        "@codemirror/view": "^6.0.0"
+      }
+    },
     "node_modules/color-convert": {
       "version": "2.0.1",
       "resolved": "https://registry.npmjs.org/color-convert/-/color-convert-2.0.1.tgz",
@@ -14766,6 +14932,12 @@
         "ieee754": "^1.1.13"
       }
     },
+    "node_modules/crelt": {
+      "version": "1.0.6",
+      "resolved": "https://registry.npmjs.org/crelt/-/crelt-1.0.6.tgz",
+      "integrity": "sha512-VQ2MBenTq1fWZUH9DJNGti7kKv6EeAuYr3cLwxUWhIu1baTaXh4Ib5W2CqHVqib4/MqbYGJqiL3Zb8GJZr3l4g==",
+      "license": "MIT"
+    },
     "node_modules/cron-parser": {
       "version": "4.9.0",
       "resolved": "https://registry.npmjs.org/cron-parser/-/cron-parser-4.9.0.tgz",
@@ -27782,6 +27954,12 @@
         "webpack": "^5.0.0"
       }
     },
+    "node_modules/style-mod": {
+      "version": "4.1.3",
+      "resolved": "https://registry.npmjs.org/style-mod/-/style-mod-4.1.3.tgz",
+      "integrity": "sha512-i/n8VsZydrugj3Iuzll8+x/00GH2vnYsk1eomD8QiRrSAeW6ItbCQDtfXCeJHd0iwiNagqjQkvpvREEPtW3IoQ==",
+      "license": "MIT"
+    },
     "node_modules/stylehacks": {
       "version": "6.1.1",
       "resolved": "https://registry.npmjs.org/stylehacks/-/stylehacks-6.1.1.tgz",
@@ -30374,6 +30552,12 @@
       "integrity": "sha512-/BpdSx+yCQGnCvecbyXdxHDkuk55/G3xwnC0GqY4gmQ3j+A+g8kzzgB4Nk/SINjqn6+waqw3EgbVF2QKExkRxQ==",
       "license": "MIT"
     },
+    "node_modules/w3c-keyname": {
+      "version": "2.2.8",
+      "resolved": "https://registry.npmjs.org/w3c-keyname/-/w3c-keyname-2.2.8.tgz",
+      "integrity": "sha512-dpojBhNsCNN7T82Tm7k26A6G9ML3NkhDsnw9n/eoxSRlVBB4CEtIQ/KTCLI2Fwf3ataSXRhYFkQi3SlnFwPvPQ==",
+      "license": "MIT"
+    },
     "node_modules/wait-on": {
       "version": "7.2.0",
       "resolved": "https://registry.npmjs.org/wait-on/-/wait-on-7.2.0.tgz",
diff --git a/package.json b/package.json
index de36c4f..f6afff6 100644
--- a/package.json
+++ b/package.json
@@ -60,6 +60,12 @@
     "@angular/forms": "^21.0.0",
     "@angular/platform-browser": "^21.0.0",
     "@angular/router": "^21.0.0",
+    "@codemirror/commands": "^6.10.3",
+    "@codemirror/lang-json": "^6.0.2",
+    "@codemirror/language": "^6.12.3",
+    "@codemirror/state": "^6.6.0",
+    "@codemirror/theme-one-dark": "^6.1.3",
+    "@codemirror/view": "^6.41.0",
     "@ng-icons/core": "^33.0.0",
     "@ng-icons/lucide": "^33.0.0",
     "@ngrx/effects": "^21.0.1",
@@ -73,6 +79,7 @@
     "auto-launch": "^5.0.6",
     "class-variance-authority": "^0.7.1",
     "clsx": "^2.1.1",
+    "codemirror": "^6.0.2",
     "cytoscape": "^3.33.1",
     "electron-updater": "^6.6.2",
     "mermaid": "^11.12.3",
diff --git a/server/data/metoyou.sqlite b/server/data/metoyou.sqlite
index f19b4c7..d146c46 100644
Binary files a/server/data/metoyou.sqlite and b/server/data/metoyou.sqlite differ
diff --git a/toju-app/angular.json b/toju-app/angular.json
index f182026..dd6ef4a 100644
--- a/toju-app/angular.json
+++ b/toju-app/angular.json
@@ -97,7 +97,7 @@
                 {
                   "type": "initial",
                   "maximumWarning": "1MB",
-                  "maximumError": "2.1MB"
+                  "maximumError": "2.15MB"
                 },
                 {
                   "type": "anyComponentStyle",
diff --git a/toju-app/src/app/app.html b/toju-app/src/app/app.html
index b2b15f4..8982483 100644
--- a/toju-app/src/app/app.html
+++ b/toju-app/src/app/app.html
@@ -1,60 +1,139 @@
-<div class="workspace-bright-theme relative flex h-screen overflow-hidden bg-background text-foreground">
-  <!-- Global left servers rail always visible -->
-  <aside class="w-16 flex-shrink-0 bg-transparent">
-    <app-servers-rail class="h-full" />
-  </aside>
-  <main class="relative min-w-0 flex-1 overflow-hidden bg-background">
-    <!-- Custom draggable title bar -->
-    <app-title-bar />
+<div
+  appThemeNode="appRoot"
+  class="workspace-bright-theme relative h-screen overflow-hidden bg-background text-foreground"
+>
+  <div
+    class="grid h-full min-h-0 min-w-0 overflow-hidden"
+    [ngStyle]="appShellLayoutStyles()"
+  >
+    <aside
+      appThemeNode="serversRail"
+      class="min-h-0 overflow-hidden bg-transparent"
+      [class.hidden]="isThemeStudioFullscreen()"
+      [ngStyle]="serversRailLayoutStyles()"
+    >
+      <app-servers-rail class="block h-full" />
+    </aside>
 
-    @if (desktopUpdateState().restartRequired) {
-    <div class="absolute inset-x-0 top-10 z-20 px-4 pt-4 pointer-events-none">
-      <div class="pointer-events-auto mx-auto max-w-4xl rounded-md border border-border bg-card p-4 shadow-sm">
-        <div class="flex flex-col gap-4 lg:flex-row lg:items-center lg:justify-between">
-          <div>
-            <p class="text-sm font-semibold text-foreground">Update ready to install</p>
-            <p class="mt-1 text-sm text-muted-foreground">
-              MetoYou {{ desktopUpdateState().targetVersion || 'update' }} has been downloaded. Restart the app to finish applying it.
-            </p>
-          </div>
+    <main
+      appThemeNode="appWorkspace"
+      class="relative flex min-h-0 min-w-0 flex-col overflow-hidden bg-background"
+      [ngStyle]="appWorkspaceShellStyles()"
+    >
+      <app-title-bar class="block shrink-0" />
 
-          <div class="flex flex-wrap gap-2">
-            <button
-              type="button"
-              (click)="openUpdatesSettings()"
-              class="inline-flex items-center rounded-md border border-border bg-secondary px-4 py-2 text-sm font-medium text-foreground transition-colors hover:bg-secondary/80"
-            >
-              Update settings
-            </button>
+      <div class="relative min-h-0 flex-1 overflow-hidden">
+        @if (isThemeStudioFullscreen()) {
+        <div class="theme-studio-fullscreen-shell absolute inset-0 overflow-y-auto overflow-x-hidden bg-background">
+          @if (themeStudioFullscreenComponent()) {
+          <ng-container *ngComponentOutlet="themeStudioFullscreenComponent()"></ng-container>
+          } @else {
+          <div class="flex h-full items-center justify-center px-6 text-sm text-muted-foreground">Loading Theme Studio…</div>
+          }
+        </div>
+        } @else { @if (desktopUpdateState().restartRequired) {
+        <div class="pointer-events-none absolute inset-x-0 top-0 z-20 px-4 pt-4">
+          <div class="pointer-events-auto mx-auto max-w-4xl rounded-md border border-border bg-card p-4 shadow-sm">
+            <div class="flex flex-col gap-4 lg:flex-row lg:items-center lg:justify-between">
+              <div>
+                <p class="text-sm font-semibold text-foreground">Update ready to install</p>
+                <p class="mt-1 text-sm text-muted-foreground">
+                  MetoYou {{ desktopUpdateState().targetVersion || 'update' }} has been downloaded. Restart the app to finish applying it.
+                </p>
+              </div>
 
-            <button
-              type="button"
-              (click)="restartToApplyUpdate()"
-              class="inline-flex items-center rounded-md bg-primary px-4 py-2 text-sm font-medium text-primary-foreground transition-colors hover:bg-primary/90"
-            >
-              Restart now
-            </button>
+              <div class="flex flex-wrap gap-2">
+                <button
+                  type="button"
+                  (click)="openUpdatesSettings()"
+                  class="inline-flex items-center rounded-md border border-border bg-secondary px-4 py-2 text-sm font-medium text-foreground transition-colors hover:bg-secondary/80"
+                >
+                  Update settings
+                </button>
+
+                <button
+                  type="button"
+                  (click)="restartToApplyUpdate()"
+                  class="inline-flex items-center rounded-md bg-primary px-4 py-2 text-sm font-medium text-primary-foreground transition-colors hover:bg-primary/90"
+                >
+                  Restart now
+                </button>
+              </div>
+            </div>
           </div>
         </div>
+        }
+
+        <div class="absolute inset-0 overflow-auto">
+          <router-outlet />
+        </div>
+        }
       </div>
-    </div>
-    }
+    </main>
+  </div>
 
-    <!-- Content area fills below the title bar without global scroll -->
-    <div class="absolute inset-x-0 top-10 bottom-0 overflow-auto">
-      <router-outlet />
-    </div>
-  </main>
+  @if (isThemeStudioFullscreen()) {
+  <div
+    #themeStudioControlsRef
+    class="pointer-events-none absolute z-[80]"
+    [ngStyle]="themeStudioControlsPositionStyles()"
+  >
+    <div class="pointer-events-auto flex items-center gap-2 rounded-full border border-border/80 bg-card/95 px-2 py-2 shadow-2xl backdrop-blur">
+      <div
+        class="rounded-full border border-border bg-background px-3 py-1.5 text-[11px] font-semibold uppercase tracking-[0.18em] text-muted-foreground select-none cursor-grab"
+        [class.cursor-grabbing]="isDraggingThemeStudioControls()"
+        (pointerdown)="startThemeStudioControlsDrag($event, themeStudioControlsRef)"
+      >
+        Theme Studio
+      </div>
 
-  <!-- Floating voice controls - shown when connected to voice and navigated away from server -->
+      <button
+        type="button"
+        (click)="minimizeThemeStudio()"
+        class="rounded-full border border-border bg-background px-3 py-1.5 text-xs font-medium text-foreground transition-colors hover:bg-secondary"
+      >
+        Minimize
+      </button>
+
+      <button
+        type="button"
+        (click)="closeThemeStudio()"
+        class="rounded-full border border-border bg-background px-3 py-1.5 text-xs font-medium text-foreground transition-colors hover:bg-secondary"
+      >
+        Close
+      </button>
+    </div>
+  </div>
+  } @if (isThemeStudioMinimized()) {
+  <div class="pointer-events-none absolute bottom-4 right-4 z-[80]">
+    <div class="pointer-events-auto flex items-center gap-3 rounded-2xl border border-border/80 bg-card/95 px-3 py-3 shadow-2xl backdrop-blur">
+      <div class="min-w-0">
+        <p class="text-[11px] font-semibold uppercase tracking-[0.18em] text-primary">Theme Studio</p>
+        <p class="mt-1 text-sm font-medium text-foreground">Minimized</p>
+      </div>
+
+      <button
+        type="button"
+        (click)="reopenThemeStudio()"
+        class="rounded-full bg-primary px-3 py-1.5 text-xs font-semibold text-primary-foreground transition-colors hover:bg-primary/90"
+      >
+        Re-open
+      </button>
+
+      <button
+        type="button"
+        (click)="dismissMinimizedThemeStudio()"
+        class="rounded-full border border-border bg-background px-3 py-1.5 text-xs font-medium text-foreground transition-colors hover:bg-secondary"
+      >
+        Dismiss
+      </button>
+    </div>
+  </div>
+  } @if (!isThemeStudioFullscreen()) {
   <app-floating-voice-controls />
+  }
+  <app-settings-modal />
+  <app-screen-share-source-picker />
+  <app-debug-console [showLauncher]="false" />
+  <app-theme-picker-overlay />
 </div>
-
-<!-- Unified Settings Modal -->
-<app-settings-modal />
-
-<!-- Shared Screen Share Source Picker -->
-<app-screen-share-source-picker />
-
-<!-- Shared Debug Console -->
-<app-debug-console [showLauncher]="false" />
diff --git a/toju-app/src/app/app.ts b/toju-app/src/app/app.ts
index 81b51f8..c0eb431 100644
--- a/toju-app/src/app/app.ts
+++ b/toju-app/src/app/app.ts
@@ -3,8 +3,12 @@ import {
   Component,
   OnInit,
   OnDestroy,
+  computed,
+  effect,
   inject,
-  HostListener
+  HostListener,
+  signal,
+  Type
 } from '@angular/core';
 import {
   Router,
@@ -37,6 +41,11 @@ import {
   STORAGE_KEY_CURRENT_USER_ID,
   STORAGE_KEY_LAST_VISITED_ROUTE
 } from './core/constants';
+import {
+  ThemeNodeDirective,
+  ThemePickerOverlayComponent,
+  ThemeService
+} from './domains/theme';
 
 @Component({
   selector: 'app-root',
@@ -48,12 +57,17 @@ import {
     FloatingVoiceControlsComponent,
     SettingsModalComponent,
     DebugConsoleComponent,
-    ScreenShareSourcePickerComponent
+    ScreenShareSourcePickerComponent,
+    ThemeNodeDirective,
+    ThemePickerOverlayComponent
   ],
   templateUrl: './app.html',
   styleUrl: './app.scss'
 })
 export class App implements OnInit, OnDestroy {
+  private static readonly THEME_STUDIO_CONTROLS_MARGIN = 16;
+  private static readonly TITLE_BAR_HEIGHT = 40;
+
   store = inject(Store);
   currentRoom = this.store.selectSignal(selectCurrentRoom);
   desktopUpdates = inject(DesktopAppUpdateService);
@@ -65,17 +79,120 @@ export class App implements OnInit, OnDestroy {
   private notifications = inject(NotificationsFacade);
   private settingsModal = inject(SettingsModalService);
   private timeSync = inject(TimeSyncService);
+  private theme = inject(ThemeService);
   private voiceSession = inject(VoiceSessionFacade);
   private externalLinks = inject(ExternalLinkService);
   private electronBridge = inject(ElectronBridgeService);
   private deepLinkCleanup: (() => void) | null = null;
+  private themeStudioControlsDragOffset: { x: number; y: number } | null = null;
+  private themeStudioControlsBounds: { width: number; height: number } | null = null;
+  readonly themeStudioFullscreenComponent = signal<Type<unknown> | null>(null);
+  readonly themeStudioControlsPosition = signal<{ x: number; y: number } | null>(null);
+  readonly isDraggingThemeStudioControls = signal(false);
+
+  readonly appShellLayoutStyles = computed(() => this.theme.getLayoutContainerStyles('appShell'));
+  readonly serversRailLayoutStyles = computed(() => this.theme.getLayoutItemStyles('serversRail'));
+  readonly appWorkspaceLayoutStyles = computed(() => this.theme.getLayoutItemStyles('appWorkspace'));
+  readonly isThemeStudioFullscreen = computed(() => {
+    return this.settingsModal.isOpen()
+      && this.settingsModal.activePage() === 'theme'
+      && this.settingsModal.themeStudioFullscreen();
+  });
+  readonly isThemeStudioMinimized = computed(() => {
+    return this.settingsModal.activePage() === 'theme'
+      && this.settingsModal.themeStudioMinimized();
+  });
+  readonly appWorkspaceShellStyles = computed(() => {
+    const workspaceStyles = this.appWorkspaceLayoutStyles();
+
+    if (!this.isThemeStudioFullscreen()) {
+      return workspaceStyles;
+    }
+
+    return {
+      ...workspaceStyles,
+      gridColumn: '1 / -1',
+      gridRow: '1 / -1'
+    };
+  });
+  readonly themeStudioControlsPositionStyles = computed(() => {
+    const position = this.themeStudioControlsPosition();
+
+    if (!position) {
+      return {
+        right: `${App.THEME_STUDIO_CONTROLS_MARGIN}px`,
+        bottom: `${App.THEME_STUDIO_CONTROLS_MARGIN}px`
+      };
+    }
+
+    return {
+      left: `${position.x}px`,
+      top: `${position.y}px`
+    };
+  });
+
+  constructor() {
+    effect(() => {
+      if (!this.isThemeStudioFullscreen() || this.themeStudioFullscreenComponent()) {
+        return;
+      }
+
+      void import('./domains/theme/feature/settings/theme-settings.component')
+        .then((module) => {
+          this.themeStudioFullscreenComponent.set(module.ThemeSettingsComponent);
+        });
+    });
+
+    effect(() => {
+      if (this.isThemeStudioFullscreen()) {
+        return;
+      }
+
+      this.isDraggingThemeStudioControls.set(false);
+      this.themeStudioControlsDragOffset = null;
+      this.themeStudioControlsBounds = null;
+    });
+  }
 
   @HostListener('document:click', ['$event'])
   onGlobalLinkClick(evt: MouseEvent): void {
     this.externalLinks.handleClick(evt);
   }
 
+  @HostListener('document:keydown', ['$event'])
+  onGlobalKeyDown(evt: KeyboardEvent): void {
+    this.theme.handleGlobalShortcut(evt);
+  }
+
+  @HostListener('document:pointermove', ['$event'])
+  onDocumentPointerMove(event: PointerEvent): void {
+    if (!this.isDraggingThemeStudioControls() || !this.themeStudioControlsDragOffset || !this.themeStudioControlsBounds) {
+      return;
+    }
+
+    this.themeStudioControlsPosition.set(this.clampThemeStudioControlsPosition(
+      event.clientX - this.themeStudioControlsDragOffset.x,
+      event.clientY - this.themeStudioControlsDragOffset.y,
+      this.themeStudioControlsBounds.width,
+      this.themeStudioControlsBounds.height
+    ));
+  }
+
+  @HostListener('document:pointerup')
+  @HostListener('document:pointercancel')
+  onDocumentPointerEnd(): void {
+    if (!this.isDraggingThemeStudioControls()) {
+      return;
+    }
+
+    this.isDraggingThemeStudioControls.set(false);
+    this.themeStudioControlsDragOffset = null;
+    this.themeStudioControlsBounds = null;
+  }
+
   async ngOnInit(): Promise<void> {
+    this.theme.initialize();
+
     void this.desktopUpdates.initialize();
 
     await this.databaseService.initialize();
@@ -143,6 +260,45 @@ export class App implements OnInit, OnDestroy {
     this.settingsModal.open('updates');
   }
 
+  startThemeStudioControlsDrag(event: PointerEvent, controlsElement: HTMLElement): void {
+    if (event.button !== 0) {
+      return;
+    }
+
+    const rect = controlsElement.getBoundingClientRect();
+
+    this.themeStudioControlsBounds = {
+      width: rect.width,
+      height: rect.height
+    };
+    this.themeStudioControlsDragOffset = {
+      x: event.clientX - rect.left,
+      y: event.clientY - rect.top
+    };
+    this.themeStudioControlsPosition.set({
+      x: rect.left,
+      y: rect.top
+    });
+    this.isDraggingThemeStudioControls.set(true);
+    event.preventDefault();
+  }
+
+  reopenThemeStudio(): void {
+    this.settingsModal.restoreMinimizedThemeStudio();
+  }
+
+  minimizeThemeStudio(): void {
+    this.settingsModal.minimizeThemeStudio();
+  }
+
+  dismissMinimizedThemeStudio(): void {
+    this.settingsModal.dismissMinimizedThemeStudio();
+  }
+
+  closeThemeStudio(): void {
+    this.settingsModal.close();
+  }
+
   async refreshDesktopUpdateContext(): Promise<void> {
     await this.desktopUpdates.refreshServerContext();
   }
@@ -151,6 +307,18 @@ export class App implements OnInit, OnDestroy {
     await this.desktopUpdates.restartToApplyUpdate();
   }
 
+  private clampThemeStudioControlsPosition(x: number, y: number, width: number, height: number): { x: number; y: number } {
+    const minX = App.THEME_STUDIO_CONTROLS_MARGIN;
+    const minY = App.TITLE_BAR_HEIGHT + App.THEME_STUDIO_CONTROLS_MARGIN;
+    const maxX = Math.max(minX, window.innerWidth - width - App.THEME_STUDIO_CONTROLS_MARGIN);
+    const maxY = Math.max(minY, window.innerHeight - height - App.THEME_STUDIO_CONTROLS_MARGIN);
+
+    return {
+      x: Math.min(Math.max(minX, x), maxX),
+      y: Math.min(Math.max(minY, y), maxY)
+    };
+  }
+
   private async setupDesktopDeepLinks(): Promise<void> {
     const electronApi = this.electronBridge.getApi();
 
diff --git a/toju-app/src/app/core/constants.ts b/toju-app/src/app/core/constants.ts
index 5ba6e31..db4bc8b 100644
--- a/toju-app/src/app/core/constants.ts
+++ b/toju-app/src/app/core/constants.ts
@@ -4,6 +4,8 @@ export const STORAGE_KEY_CONNECTION_SETTINGS = 'metoyou_connection_settings';
 export const STORAGE_KEY_NOTIFICATION_SETTINGS = 'metoyou_notification_settings';
 export const STORAGE_KEY_VOICE_SETTINGS = 'metoyou_voice_settings';
 export const STORAGE_KEY_DEBUGGING_SETTINGS = 'metoyou_debugging_settings';
+export const STORAGE_KEY_THEME_ACTIVE = 'metoyou_theme_active';
+export const STORAGE_KEY_THEME_DRAFT = 'metoyou_theme_draft';
 export const STORAGE_KEY_USER_VOLUMES = 'metoyou_user_volumes';
 export const ROOM_URL_PATTERN = /\/room\/([^/]+)/;
 export const STORE_DEVTOOLS_MAX_AGE = 25;
diff --git a/toju-app/src/app/core/platform/electron/electron-api.models.ts b/toju-app/src/app/core/platform/electron/electron-api.models.ts
index defb1fc..65d34e2 100644
--- a/toju-app/src/app/core/platform/electron/electron-api.models.ts
+++ b/toju-app/src/app/core/platform/electron/electron-api.models.ts
@@ -118,6 +118,12 @@ export interface WindowStateSnapshot {
   isMinimized: boolean;
 }
 
+export interface SavedThemeFileDescriptor {
+  fileName: string;
+  modifiedAt: number;
+  path: string;
+}
+
 export interface ElectronCommand {
   type: string;
   payload: unknown;
@@ -143,6 +149,11 @@ export interface ElectronApi {
   onLinuxScreenShareMonitorAudioChunk: (listener: (payload: LinuxScreenShareMonitorAudioChunkPayload) => void) => () => void;
   onLinuxScreenShareMonitorAudioEnded: (listener: (payload: LinuxScreenShareMonitorAudioEndedPayload) => void) => () => void;
   getAppDataPath: () => Promise<string>;
+  getSavedThemesPath: () => Promise<string>;
+  listSavedThemes: () => Promise<SavedThemeFileDescriptor[]>;
+  readSavedTheme: (fileName: string) => Promise<string>;
+  writeSavedTheme: (fileName: string, text: string) => Promise<boolean>;
+  deleteSavedTheme: (fileName: string) => Promise<boolean>;
   consumePendingDeepLink: () => Promise<string | null>;
   getDesktopSettings: () => Promise<DesktopSettingsSnapshot>;
   showDesktopNotification: (payload: DesktopNotificationPayload) => Promise<boolean>;
diff --git a/toju-app/src/app/core/services/settings-modal.service.ts b/toju-app/src/app/core/services/settings-modal.service.ts
index dcfb525..03349fb 100644
--- a/toju-app/src/app/core/services/settings-modal.service.ts
+++ b/toju-app/src/app/core/services/settings-modal.service.ts
@@ -2,6 +2,7 @@ import { Injectable, signal } from '@angular/core';
 
 export type SettingsPage =
   | 'general'
+  | 'theme'
   | 'network'
   | 'notifications'
   | 'voice'
@@ -17,18 +18,59 @@ export class SettingsModalService {
   readonly isOpen = signal(false);
   readonly activePage = signal<SettingsPage>('general');
   readonly targetServerId = signal<string | null>(null);
+  readonly themeStudioFullscreen = signal(false);
+  readonly themeStudioMinimized = signal(false);
 
   open(page: SettingsPage = 'general', serverId?: string): void {
+    this.themeStudioFullscreen.set(false);
+    this.themeStudioMinimized.set(false);
     this.activePage.set(page);
     this.targetServerId.set(serverId ?? null);
     this.isOpen.set(true);
   }
 
   close(): void {
+    this.themeStudioFullscreen.set(false);
+    this.themeStudioMinimized.set(false);
     this.isOpen.set(false);
   }
 
   navigate(page: SettingsPage): void {
     this.activePage.set(page);
+
+    if (page !== 'theme') {
+      this.themeStudioFullscreen.set(false);
+      this.themeStudioMinimized.set(false);
+    }
+  }
+
+  setThemeStudioFullscreen(isFullscreen: boolean): void {
+    this.themeStudioFullscreen.set(isFullscreen);
+  }
+
+  toggleThemeStudioFullscreen(): void {
+    this.themeStudioFullscreen.update((isFullscreen) => !isFullscreen);
+  }
+
+  openThemeStudio(): void {
+    this.activePage.set('theme');
+    this.themeStudioMinimized.set(false);
+    this.isOpen.set(true);
+    this.themeStudioFullscreen.set(true);
+  }
+
+  minimizeThemeStudio(): void {
+    this.activePage.set('theme');
+    this.themeStudioFullscreen.set(false);
+    this.themeStudioMinimized.set(true);
+    this.isOpen.set(false);
+  }
+
+  restoreMinimizedThemeStudio(): void {
+    this.openThemeStudio();
+  }
+
+  dismissMinimizedThemeStudio(): void {
+    this.themeStudioMinimized.set(false);
   }
 }
diff --git a/toju-app/src/app/domains/README.md b/toju-app/src/app/domains/README.md
index 673fa87..96e4352 100644
--- a/toju-app/src/app/domains/README.md
+++ b/toju-app/src/app/domains/README.md
@@ -14,6 +14,7 @@ infrastructure adapters and UI.
 | **notifications** | Notification preferences, unread tracking, desktop alert orchestration | `NotificationsFacade` |
 | **screen-share** | Source picker, quality presets | `ScreenShareFacade` |
 | **server-directory** | Multi-server endpoint management, health checks, invites, server search UI | `ServerDirectoryFacade` |
+| **theme** | JSON-driven theming, element registry, layout syncing, picker tooling, and Electron saved-theme library management | `ThemeService` |
 | **voice-connection** | Voice activity detection, bitrate profiles, in-channel camera transport | `VoiceConnectionFacade` |
 | **voice-session** | Join/leave orchestration, voice settings persistence | `VoiceSessionFacade` |
 
diff --git a/toju-app/src/app/domains/theme/application/element-picker.service.ts b/toju-app/src/app/domains/theme/application/element-picker.service.ts
new file mode 100644
index 0000000..cf136f7
--- /dev/null
+++ b/toju-app/src/app/domains/theme/application/element-picker.service.ts
@@ -0,0 +1,132 @@
+import { DOCUMENT } from '@angular/common';
+import { Injectable, inject, signal } from '@angular/core';
+
+import {
+  SettingsModalService,
+  type SettingsPage
+} from '../../../core/services/settings-modal.service';
+import { ThemeRegistryService } from './theme-registry.service';
+
+@Injectable({ providedIn: 'root' })
+export class ElementPickerService {
+  private readonly documentRef = inject(DOCUMENT);
+  private readonly modal = inject(SettingsModalService);
+  private readonly registry = inject(ThemeRegistryService);
+
+  private removeListeners: Array<() => void> = [];
+  private resumePage: SettingsPage | null = null;
+  private shouldRestoreModalOnCancel = true;
+
+  readonly isPicking = signal(false);
+  readonly hoveredKey = signal<string | null>(null);
+  readonly selectedKey = signal<string | null>(null);
+
+  start(page: SettingsPage = 'theme', restoreModalOnCancel = true): void {
+    if (this.isPicking()) {
+      return;
+    }
+
+    this.resumePage = page;
+    this.shouldRestoreModalOnCancel = restoreModalOnCancel;
+    this.modal.close();
+    this.attachListeners();
+    this.hoveredKey.set(null);
+    this.isPicking.set(true);
+  }
+
+  cancel(): void {
+    if (!this.isPicking()) {
+      return;
+    }
+
+    this.detachListeners();
+    this.hoveredKey.set(null);
+    this.isPicking.set(false);
+
+    if (this.shouldRestoreModalOnCancel && this.resumePage) {
+      this.modal.open(this.resumePage);
+    }
+  }
+
+  clearSelection(): void {
+    this.selectedKey.set(null);
+  }
+
+  private completePick(key: string): void {
+    this.selectedKey.set(key);
+    this.detachListeners();
+    this.hoveredKey.set(null);
+    this.isPicking.set(false);
+
+    if (this.resumePage) {
+      this.modal.open(this.resumePage);
+    }
+  }
+
+  private attachListeners(): void {
+    const onPointerMove = (event: Event) => {
+      const key = this.resolveThemeKeyFromTarget(event.target);
+
+      this.hoveredKey.set(key);
+    };
+
+    const onClick = (event: Event) => {
+      const key = this.resolveThemeKeyFromTarget(event.target);
+
+      if (!key) {
+        return;
+      }
+
+      event.preventDefault();
+      event.stopPropagation();
+
+      if ('stopImmediatePropagation' in event) {
+        (event as Event & { stopImmediatePropagation(): void }).stopImmediatePropagation();
+      }
+
+      this.completePick(key);
+    };
+
+    const onKeyDown = (event: Event) => {
+      const keyboardEvent = event as KeyboardEvent;
+
+      if (keyboardEvent.key === 'Escape') {
+        keyboardEvent.preventDefault();
+        keyboardEvent.stopPropagation();
+        this.cancel();
+      }
+    };
+
+    this.documentRef.addEventListener('pointermove', onPointerMove, true);
+    this.documentRef.addEventListener('click', onClick, true);
+    this.documentRef.addEventListener('keydown', onKeyDown, true);
+
+    this.removeListeners = [
+      () => this.documentRef.removeEventListener('pointermove', onPointerMove, true),
+      () => this.documentRef.removeEventListener('click', onClick, true),
+      () => this.documentRef.removeEventListener('keydown', onKeyDown, true)
+    ];
+  }
+
+  private detachListeners(): void {
+    for (const removeListener of this.removeListeners) {
+      removeListener();
+    }
+
+    this.removeListeners = [];
+  }
+
+  private resolveThemeKeyFromTarget(target: EventTarget | null): string | null {
+    if (!(target instanceof Element)) {
+      return null;
+    }
+
+    const themedElement = target.closest<HTMLElement>('[data-theme-key]');
+    const key = themedElement?.dataset['themeKey'] ?? null;
+    const definition = this.registry.getDefinition(key);
+
+    return definition?.pickerVisible
+      ? key
+      : null;
+  }
+}
\ No newline at end of file
diff --git a/toju-app/src/app/domains/theme/application/layout-sync.service.ts b/toju-app/src/app/domains/theme/application/layout-sync.service.ts
new file mode 100644
index 0000000..8ebead8
--- /dev/null
+++ b/toju-app/src/app/domains/theme/application/layout-sync.service.ts
@@ -0,0 +1,58 @@
+import { Injectable, computed, inject } from '@angular/core';
+
+import {
+  ThemeContainerKey,
+  ThemeGridEditorItem,
+  ThemeGridRect
+} from '../domain/theme.models';
+import { createDefaultThemeDocument } from '../domain/theme.defaults';
+import { ThemeRegistryService } from './theme-registry.service';
+import { ThemeService } from './theme.service';
+
+@Injectable({ providedIn: 'root' })
+export class LayoutSyncService {
+  private readonly registry = inject(ThemeRegistryService);
+  private readonly theme = inject(ThemeService);
+
+  readonly draftLayout = computed(() => this.theme.draftTheme().layout);
+
+  containers() {
+    return this.registry.layoutContainers();
+  }
+
+  itemsForContainer(containerKey: ThemeContainerKey): ThemeGridEditorItem[] {
+    const draftTheme = this.theme.draftTheme();
+    const defaults = createDefaultThemeDocument();
+
+    return this.registry.entries()
+      .filter((entry) => entry.layoutEditable && entry.container === containerKey)
+      .map((entry) => ({
+        key: entry.key,
+        label: entry.label,
+        description: entry.description,
+        grid: draftTheme.layout[entry.key]?.grid ?? defaults.layout[entry.key].grid
+      }));
+  }
+
+  updateGrid(key: string, grid: ThemeGridRect): void {
+    this.theme.ensureLayoutEntry(key);
+    this.theme.updateStructuredDraft((draft: ReturnType<typeof createDefaultThemeDocument>) => {
+      draft.layout[key] = {
+        ...draft.layout[key],
+        grid
+      };
+    }, true, `${key} layout updated.`);
+  }
+
+  resetContainer(containerKey: ThemeContainerKey): void {
+    const defaults = createDefaultThemeDocument();
+
+    this.theme.updateStructuredDraft((draft: ReturnType<typeof createDefaultThemeDocument>) => {
+      for (const entry of this.registry.entries()) {
+        if (entry.container === containerKey && entry.layoutEditable) {
+          draft.layout[entry.key] = defaults.layout[entry.key];
+        }
+      }
+    }, true, `${containerKey} restored to its default layout.`);
+  }
+}
\ No newline at end of file
diff --git a/toju-app/src/app/domains/theme/application/theme-library.service.ts b/toju-app/src/app/domains/theme/application/theme-library.service.ts
new file mode 100644
index 0000000..0e12963
--- /dev/null
+++ b/toju-app/src/app/domains/theme/application/theme-library.service.ts
@@ -0,0 +1,176 @@
+import { Injectable, computed, inject, signal } from '@angular/core';
+import type { SavedThemeSummary } from '../domain/theme.models';
+import { ThemeLibraryStorageService } from '../infrastructure/theme-library.storage';
+import { ThemeService } from './theme.service';
+
+@Injectable({ providedIn: 'root' })
+export class ThemeLibraryService {
+  private readonly storage = inject(ThemeLibraryStorageService);
+  private readonly theme = inject(ThemeService);
+
+  readonly isAvailable = signal(this.storage.isAvailable);
+  readonly entries = signal<SavedThemeSummary[]>([]);
+  readonly selectedFileName = signal<string | null>(null);
+  readonly isBusy = signal(false);
+  readonly savedThemesPath = signal<string | null>(null);
+  readonly selectedEntry = computed(() => {
+    const selectedFileName = this.selectedFileName();
+
+    return selectedFileName
+      ? this.entries().find((entry) => entry.fileName === selectedFileName) ?? null
+      : null;
+  });
+
+  async refresh(preferredSelection?: string | null): Promise<void> {
+    if (!this.isAvailable() || this.isBusy()) {
+      return;
+    }
+
+    this.isBusy.set(true);
+
+    try {
+      await this.refreshEntries(preferredSelection);
+    } catch {
+      this.theme.announceStatus('Unable to refresh the saved themes library.');
+    } finally {
+      this.isBusy.set(false);
+    }
+  }
+
+  select(fileName: string | null): void {
+    this.selectedFileName.set(fileName);
+  }
+
+  async useSelectedTheme(): Promise<boolean> {
+    const selectedEntry = this.selectedEntry();
+
+    if (!selectedEntry || this.isBusy()) {
+      return false;
+    }
+
+    const themeText = await this.storage.readThemeText(selectedEntry.fileName);
+
+    if (!themeText) {
+      this.theme.announceStatus('Unable to read the selected saved theme.');
+      return false;
+    }
+
+    return this.theme.loadThemeText(themeText, 'apply', `${selectedEntry.themeName} applied from saved themes.`, 'saved theme');
+  }
+
+  async openSelectedThemeInDraft(): Promise<boolean> {
+    const selectedEntry = this.selectedEntry();
+
+    if (!selectedEntry || this.isBusy()) {
+      return false;
+    }
+
+    const themeText = await this.storage.readThemeText(selectedEntry.fileName);
+
+    if (!themeText) {
+      this.theme.announceStatus('Unable to read the selected saved theme.');
+      return false;
+    }
+
+    return this.theme.loadThemeText(themeText, 'draft', `${selectedEntry.themeName} loaded into the draft editor.`, 'saved theme');
+  }
+
+  async saveDraftAsNewTheme(): Promise<string | null> {
+    if (this.isBusy()) {
+      return null;
+    }
+
+    if (!this.theme.draftIsValid()) {
+      this.theme.announceStatus('Fix JSON errors before saving a theme.');
+      return null;
+    }
+
+    this.isBusy.set(true);
+
+    try {
+      const fileName = await this.storage.saveNewTheme(this.theme.draftTheme().meta.name, this.theme.draftText());
+
+      if (!fileName) {
+        this.theme.announceStatus('Unable to save the current draft as a new theme.');
+        return null;
+      }
+
+      await this.refreshEntries(fileName);
+      this.theme.announceStatus(`${this.theme.draftTheme().meta.name} saved to the Electron themes folder.`);
+      return fileName;
+    } finally {
+      this.isBusy.set(false);
+    }
+  }
+
+  async saveDraftToSelectedTheme(): Promise<boolean> {
+    const selectedEntry = this.selectedEntry();
+
+    if (!selectedEntry || this.isBusy()) {
+      return false;
+    }
+
+    if (!this.theme.draftIsValid()) {
+      this.theme.announceStatus('Fix JSON errors before updating a saved theme.');
+      return false;
+    }
+
+    this.isBusy.set(true);
+
+    try {
+      const saved = await this.storage.overwriteTheme(selectedEntry.fileName, this.theme.draftText());
+
+      if (!saved) {
+        this.theme.announceStatus('Unable to update the selected saved theme.');
+        return false;
+      }
+
+      await this.refreshEntries(selectedEntry.fileName);
+      this.theme.announceStatus(`${selectedEntry.themeName} updated in the Electron themes folder.`);
+      return true;
+    } finally {
+      this.isBusy.set(false);
+    }
+  }
+
+  async removeSelectedTheme(): Promise<boolean> {
+    const selectedEntry = this.selectedEntry();
+
+    if (!selectedEntry || this.isBusy()) {
+      return false;
+    }
+
+    this.isBusy.set(true);
+
+    try {
+      const deleted = await this.storage.deleteTheme(selectedEntry.fileName);
+
+      if (!deleted) {
+        this.theme.announceStatus('Unable to remove the selected saved theme.');
+        return false;
+      }
+
+      await this.refreshEntries(null);
+      this.theme.announceStatus(`${selectedEntry.themeName} removed from saved themes.`);
+      return true;
+    } finally {
+      this.isBusy.set(false);
+    }
+  }
+
+  private async refreshEntries(preferredSelection?: string | null): Promise<void> {
+    const entries = await this.storage.listThemes();
+    const savedThemesPath = await this.storage.getSavedThemesPath();
+    const nextSelection = preferredSelection ?? this.selectedFileName();
+
+    this.entries.set(entries);
+    this.savedThemesPath.set(savedThemesPath);
+
+    if (nextSelection && entries.some((entry) => entry.fileName === nextSelection)) {
+      this.selectedFileName.set(nextSelection);
+      return;
+    }
+
+    this.selectedFileName.set(entries[0]?.fileName ?? null);
+  }
+}
\ No newline at end of file
diff --git a/toju-app/src/app/domains/theme/application/theme-registry.service.ts b/toju-app/src/app/domains/theme/application/theme-registry.service.ts
new file mode 100644
index 0000000..cb68dc3
--- /dev/null
+++ b/toju-app/src/app/domains/theme/application/theme-registry.service.ts
@@ -0,0 +1,88 @@
+import { Injectable, signal } from '@angular/core';
+
+import {
+  ThemeLayoutContainerDefinition,
+  ThemeRegistryEntry
+} from '../domain/theme.models';
+import {
+  THEME_LAYOUT_CONTAINERS,
+  THEME_REGISTRY,
+  findThemeLayoutContainer,
+  findThemeRegistryEntry
+} from '../domain/theme.registry';
+
+@Injectable({ providedIn: 'root' })
+export class ThemeRegistryService {
+  private readonly mountedCounts = signal<Record<string, number>>({});
+  private readonly mountedHosts = new Map<string, Set<HTMLElement>>();
+
+  entries(): readonly ThemeRegistryEntry[] {
+    return THEME_REGISTRY;
+  }
+
+  layoutContainers(): readonly ThemeLayoutContainerDefinition[] {
+    return THEME_LAYOUT_CONTAINERS;
+  }
+
+  mountedKeyCounts() {
+    return this.mountedCounts();
+  }
+
+  getDefinition(key: string | null | undefined): ThemeRegistryEntry | null {
+    return key
+      ? findThemeRegistryEntry(key)
+      : null;
+  }
+
+  getContainer(key: string | null | undefined): ThemeLayoutContainerDefinition | null {
+    return key
+      ? findThemeLayoutContainer(key)
+      : null;
+  }
+
+  registerHost(key: string, host: HTMLElement): void {
+    const existingHosts = this.mountedHosts.get(key) ?? new Set<HTMLElement>();
+
+    existingHosts.add(host);
+    this.mountedHosts.set(key, existingHosts);
+    this.syncMountedCounts();
+  }
+
+  unregisterHost(key: string, host: HTMLElement): void {
+    const existingHosts = this.mountedHosts.get(key);
+
+    if (!existingHosts) {
+      return;
+    }
+
+    existingHosts.delete(host);
+
+    if (existingHosts.size === 0) {
+      this.mountedHosts.delete(key);
+    }
+
+    this.syncMountedCounts();
+  }
+
+  firstMountedHost(key: string): HTMLElement | null {
+    const hosts = this.mountedHosts.get(key);
+
+    return hosts
+      ? Array.from(hosts)[0] ?? null
+      : null;
+  }
+
+  isMounted(key: string): boolean {
+    return (this.mountedCounts()[key] ?? 0) > 0;
+  }
+
+  private syncMountedCounts(): void {
+    const nextCounts: Record<string, number> = {};
+
+    for (const [key, hosts] of this.mountedHosts.entries()) {
+      nextCounts[key] = hosts.size;
+    }
+
+    this.mountedCounts.set(nextCounts);
+  }
+}
\ No newline at end of file
diff --git a/toju-app/src/app/domains/theme/application/theme.service.ts b/toju-app/src/app/domains/theme/application/theme.service.ts
new file mode 100644
index 0000000..2214590
--- /dev/null
+++ b/toju-app/src/app/domains/theme/application/theme.service.ts
@@ -0,0 +1,515 @@
+import { DOCUMENT } from '@angular/common';
+import { Injectable, computed, inject, signal } from '@angular/core';
+
+import {
+  ThemeAnimationDefinition,
+  ThemeContainerKey,
+  ThemeDocument,
+  ThemeElementStyleProperty,
+  ThemeElementStyles
+} from '../domain/theme.models';
+import {
+  DEFAULT_THEME_JSON,
+  createDefaultThemeDocument,
+  isLegacyDefaultThemeDocument
+} from '../domain/theme.defaults';
+import {
+  createAnimationStarterDefinition
+} from '../domain/theme.schema';
+import {
+  findThemeLayoutContainer
+} from '../domain/theme.registry';
+import { validateThemeDocument } from '../domain/theme.validation';
+import {
+  loadThemeStorageSnapshot,
+  saveActiveThemeText,
+  saveDraftThemeText
+} from '../infrastructure/theme.storage';
+
+function toKebabCase(value: string): string {
+  return value
+    .replace(/([a-z0-9])([A-Z])/g, '$1-$2')
+    .replace(/[_\s]+/g, '-')
+    .toLowerCase();
+}
+
+function stringifyTheme(document: ThemeDocument): string {
+  return JSON.stringify(document, null, 2);
+}
+
+function resolveBuiltInDefaultMigration(document: ThemeDocument): ThemeDocument {
+  return isLegacyDefaultThemeDocument(document)
+    ? createDefaultThemeDocument()
+    : document;
+}
+
+@Injectable({ providedIn: 'root' })
+export class ThemeService {
+  private readonly documentRef = inject(DOCUMENT);
+
+  private readonly activeThemeInternal = signal<ThemeDocument>(createDefaultThemeDocument());
+  private readonly activeThemeTextInternal = signal(DEFAULT_THEME_JSON);
+  private readonly draftThemeInternal = signal<ThemeDocument>(createDefaultThemeDocument());
+  private readonly draftTextInternal = signal(DEFAULT_THEME_JSON);
+  private readonly draftIsValidInternal = signal(true);
+  private readonly draftErrorsInternal = signal<string[]>([]);
+  private readonly statusMessageInternal = signal<string | null>(null);
+
+  private initialized = false;
+  private statusTimeoutId: ReturnType<typeof setTimeout> | null = null;
+  private animationStyleElement: HTMLStyleElement | null = null;
+
+  readonly activeTheme = this.activeThemeInternal.asReadonly();
+  readonly activeThemeText = this.activeThemeTextInternal.asReadonly();
+  readonly draftTheme = this.draftThemeInternal.asReadonly();
+  readonly draftText = this.draftTextInternal.asReadonly();
+  readonly draftIsValid = this.draftIsValidInternal.asReadonly();
+  readonly draftErrors = this.draftErrorsInternal.asReadonly();
+  readonly statusMessage = this.statusMessageInternal.asReadonly();
+  readonly activeThemeName = computed(() => this.activeThemeInternal().meta.name);
+  readonly knownAnimationClasses = computed(() => Object.keys(this.draftThemeInternal().animations));
+  readonly isDraftDirty = computed(() => {
+    return this.draftTextInternal().trim() !== this.activeThemeTextInternal().trim();
+  });
+
+  initialize(): void {
+    if (this.initialized) {
+      return;
+    }
+
+    this.initialized = true;
+
+    const storageSnapshot = loadThemeStorageSnapshot();
+    const activeText = storageSnapshot.activeText ?? DEFAULT_THEME_JSON;
+    const activeResult = this.parseAndValidateTheme(activeText, 'saved active theme');
+
+    if (activeResult.valid && activeResult.value) {
+      const resolvedTheme = resolveBuiltInDefaultMigration(activeResult.value);
+      const formatted = stringifyTheme(resolvedTheme);
+
+      this.activeThemeInternal.set(resolvedTheme);
+      this.activeThemeTextInternal.set(formatted);
+      saveActiveThemeText(formatted);
+    } else {
+      const defaultTheme = createDefaultThemeDocument();
+      const defaultText = stringifyTheme(defaultTheme);
+
+      this.activeThemeInternal.set(defaultTheme);
+      this.activeThemeTextInternal.set(defaultText);
+      saveActiveThemeText(defaultText);
+    }
+
+    const draftText = storageSnapshot.draftText ?? this.activeThemeTextInternal();
+    const draftResult = this.parseAndValidateTheme(draftText, 'saved draft theme');
+
+    if (draftResult.valid && draftResult.value) {
+      const resolvedDraftTheme = resolveBuiltInDefaultMigration(draftResult.value);
+      const formattedDraft = stringifyTheme(resolvedDraftTheme);
+
+      this.draftThemeInternal.set(resolvedDraftTheme);
+      this.draftTextInternal.set(formattedDraft);
+      this.draftIsValidInternal.set(true);
+      this.draftErrorsInternal.set([]);
+      saveDraftThemeText(formattedDraft);
+    } else {
+      this.draftThemeInternal.set(this.activeThemeInternal());
+      this.draftTextInternal.set(this.activeThemeTextInternal());
+      this.draftIsValidInternal.set(false);
+      this.draftErrorsInternal.set(draftResult.errors);
+    }
+
+    this.syncAnimationStylesheet();
+  }
+
+  updateDraftText(text: string): void {
+    this.draftTextInternal.set(text);
+    saveDraftThemeText(text);
+
+    const result = this.parseAndValidateTheme(text, 'theme draft');
+
+    if (result.valid && result.value) {
+      this.draftThemeInternal.set(result.value);
+      this.draftIsValidInternal.set(true);
+      this.draftErrorsInternal.set([]);
+      return;
+    }
+
+    this.draftIsValidInternal.set(false);
+    this.draftErrorsInternal.set(result.errors);
+  }
+
+  formatDraft(): void {
+    if (!this.draftIsValidInternal()) {
+      this.setStatusMessage('Fix JSON errors before formatting the theme draft.');
+      return;
+    }
+
+    const formatted = stringifyTheme(this.draftThemeInternal());
+
+    this.draftTextInternal.set(formatted);
+    saveDraftThemeText(formatted);
+    this.setStatusMessage('Theme draft formatted.');
+  }
+
+  applyDraft(): boolean {
+    if (!this.draftIsValidInternal()) {
+      this.setStatusMessage('The current draft has validation errors. The previous working theme is still active.');
+      return false;
+    }
+
+    const formatted = stringifyTheme(this.draftThemeInternal());
+
+    this.commitTheme(this.draftThemeInternal(), formatted, 'Theme applied.');
+    return true;
+  }
+
+  loadThemeText(
+    text: string,
+    mode: 'draft' | 'apply',
+    successMessage: string,
+    sourceLabel = 'theme'
+  ): boolean {
+    const result = this.parseAndValidateTheme(text, sourceLabel);
+
+    if (!result.valid || !result.value) {
+      this.setStatusMessage(result.errors[0] ?? `The ${sourceLabel} could not be loaded.`);
+      return false;
+    }
+
+    const resolvedTheme = resolveBuiltInDefaultMigration(result.value);
+    const formatted = stringifyTheme(resolvedTheme);
+
+    if (mode === 'apply') {
+      this.commitTheme(resolvedTheme, formatted, successMessage);
+      return true;
+    }
+
+    this.draftThemeInternal.set(resolvedTheme);
+    this.draftTextInternal.set(formatted);
+    this.draftIsValidInternal.set(true);
+    this.draftErrorsInternal.set([]);
+    saveDraftThemeText(formatted);
+    this.setStatusMessage(successMessage);
+    return true;
+  }
+
+  announceStatus(message: string): void {
+    this.setStatusMessage(message);
+  }
+
+  resetToDefault(reason: 'button' | 'shortcut' = 'button'): void {
+    const defaultTheme = createDefaultThemeDocument();
+    const defaultText = stringifyTheme(defaultTheme);
+
+    this.activeThemeInternal.set(defaultTheme);
+    this.activeThemeTextInternal.set(defaultText);
+    this.draftThemeInternal.set(defaultTheme);
+    this.draftTextInternal.set(defaultText);
+    this.draftIsValidInternal.set(true);
+    this.draftErrorsInternal.set([]);
+    saveActiveThemeText(defaultText);
+    saveDraftThemeText(defaultText);
+    this.syncAnimationStylesheet();
+    this.setStatusMessage(reason === 'shortcut'
+      ? 'Theme reset to the default preset by shortcut.'
+      : 'Theme reset to the default preset.');
+  }
+
+  handleGlobalShortcut(event: KeyboardEvent): boolean {
+    const usesModifier = event.ctrlKey || event.metaKey;
+
+    if (!usesModifier || !event.shiftKey || event.code !== 'Digit0') {
+      return false;
+    }
+
+    event.preventDefault();
+    this.resetToDefault('shortcut');
+    return true;
+  }
+
+  ensureElementEntry(key: string): void {
+    this.updateStructuredDraft((draft) => {
+      draft.elements[key] = draft.elements[key] ?? {};
+    }, false, `Prepared ${key} in the theme draft.`);
+  }
+
+  ensureLayoutEntry(key: string): void {
+    this.updateStructuredDraft((draft) => {
+      const defaults = createDefaultThemeDocument();
+
+      draft.layout[key] = draft.layout[key] ?? defaults.layout[key];
+    }, false, `Prepared ${key} layout in the theme draft.`);
+  }
+
+  setElementStyle(
+    key: string,
+    property: ThemeElementStyleProperty,
+    value: string | number,
+    applyImmediately = true
+  ): void {
+    this.updateStructuredDraft((draft) => {
+      draft.elements[key] = {
+        ...draft.elements[key],
+        [property]: value
+      };
+    }, applyImmediately, `${key} updated.`);
+  }
+
+  setAnimation(
+    key: string,
+    definition: ThemeAnimationDefinition = createAnimationStarterDefinition(),
+    applyImmediately = true
+  ): void {
+    this.updateStructuredDraft((draft) => {
+      draft.animations[key] = definition;
+    }, applyImmediately, `Animation ${key} updated.`);
+  }
+
+  getHostStyles(key: string): Record<string, string> {
+    const elementTheme = this.activeThemeInternal().elements[key] ?? {};
+    const styles: Record<string, string> = {};
+
+    if (key === 'appRoot') {
+      Object.assign(styles, this.buildTokenStyles(this.activeThemeInternal()));
+    }
+
+    const backgroundLayers = [elementTheme.gradient, elementTheme.backgroundImage]
+      .filter((layer): layer is string => typeof layer === 'string' && layer.trim().length > 0);
+
+    if (backgroundLayers.length > 0) {
+      styles['backgroundImage'] = backgroundLayers.join(', ');
+    }
+
+    if (elementTheme.width) styles['width'] = elementTheme.width;
+    if (elementTheme.height) styles['height'] = elementTheme.height;
+    if (elementTheme.minWidth) styles['minWidth'] = elementTheme.minWidth;
+    if (elementTheme.minHeight) styles['minHeight'] = elementTheme.minHeight;
+    if (elementTheme.maxWidth) styles['maxWidth'] = elementTheme.maxWidth;
+    if (elementTheme.maxHeight) styles['maxHeight'] = elementTheme.maxHeight;
+    if (elementTheme.position) styles['position'] = elementTheme.position;
+    if (elementTheme.top) styles['top'] = elementTheme.top;
+    if (elementTheme.right) styles['right'] = elementTheme.right;
+    if (elementTheme.bottom) styles['bottom'] = elementTheme.bottom;
+    if (elementTheme.left) styles['left'] = elementTheme.left;
+    if (elementTheme.padding) styles['padding'] = elementTheme.padding;
+    if (elementTheme.margin) styles['margin'] = elementTheme.margin;
+    if (elementTheme.border) styles['border'] = elementTheme.border;
+    if (elementTheme.borderRadius) styles['borderRadius'] = elementTheme.borderRadius;
+    if (elementTheme.backgroundColor) styles['backgroundColor'] = elementTheme.backgroundColor;
+    if (elementTheme.color) styles['color'] = elementTheme.color;
+    if (elementTheme.backgroundSize) styles['backgroundSize'] = elementTheme.backgroundSize;
+    if (elementTheme.backgroundPosition) styles['backgroundPosition'] = elementTheme.backgroundPosition;
+    if (elementTheme.backgroundRepeat) styles['backgroundRepeat'] = elementTheme.backgroundRepeat;
+    if (elementTheme.boxShadow) styles['boxShadow'] = elementTheme.boxShadow;
+    if (elementTheme.backdropFilter) styles['backdropFilter'] = elementTheme.backdropFilter;
+
+    if (typeof elementTheme.opacity === 'number') {
+      styles['opacity'] = `${elementTheme.opacity}`;
+    }
+
+    return styles;
+  }
+
+  getAnimationClass(key: string): string | null {
+    const animationClass = this.activeThemeInternal().elements[key]?.animationClass?.trim();
+
+    return animationClass && animationClass.length > 0
+      ? animationClass
+      : null;
+  }
+
+  getLink(key: string): string | null {
+    return this.activeThemeInternal().elements[key]?.link ?? null;
+  }
+
+  getTextOverride(key: string): string | null {
+    return this.activeThemeInternal().elements[key]?.textOverride ?? null;
+  }
+
+  getIcon(key: string): string | null {
+    return this.activeThemeInternal().elements[key]?.icon ?? null;
+  }
+
+  getLayoutContainerStyles(containerKey: ThemeContainerKey): Record<string, string> {
+    const container = findThemeLayoutContainer(containerKey);
+
+    if (!container) {
+      return {
+        display: 'grid'
+      };
+    }
+
+    return {
+      display: 'grid',
+      gridTemplateColumns: container.templateColumns ?? `repeat(${container.columns}, minmax(0, 1fr))`,
+      gridTemplateRows: container.templateRows ?? (container.rows === 1
+        ? 'minmax(0, 1fr)'
+        : `repeat(${container.rows}, minmax(0, 1fr))`),
+      minHeight: '0',
+      minWidth: '0'
+    };
+  }
+
+  getLayoutItemStyles(key: string): Record<string, string> {
+    const defaults = createDefaultThemeDocument();
+    const layoutEntry = this.activeThemeInternal().layout[key] ?? defaults.layout[key];
+
+    if (!layoutEntry) {
+      return {};
+    }
+
+    return {
+      gridColumn: `${layoutEntry.grid.x + 1} / span ${layoutEntry.grid.w}`,
+      gridRow: `${layoutEntry.grid.y + 1} / span ${layoutEntry.grid.h}`,
+      minWidth: '0',
+      minHeight: '0'
+    };
+  }
+
+  updateStructuredDraft(
+    mutator: (draft: ThemeDocument) => void,
+    applyImmediately: boolean,
+    successMessage: string
+  ): void {
+    if (!this.draftIsValidInternal()) {
+      this.setStatusMessage('Fix JSON errors before using the structured theme tools.');
+      return;
+    }
+
+    const nextDraft = structuredClone(this.draftThemeInternal());
+
+    mutator(nextDraft);
+
+    const result = validateThemeDocument(nextDraft);
+
+    if (!result.valid || !result.value) {
+      this.setStatusMessage('The structured change could not be validated.');
+      return;
+    }
+
+    const formatted = stringifyTheme(result.value);
+
+    this.draftThemeInternal.set(result.value);
+    this.draftTextInternal.set(formatted);
+    this.draftIsValidInternal.set(true);
+    this.draftErrorsInternal.set([]);
+    saveDraftThemeText(formatted);
+
+    if (applyImmediately) {
+      this.commitTheme(result.value, formatted, successMessage);
+      return;
+    }
+
+    this.setStatusMessage(successMessage);
+  }
+
+  private commitTheme(theme: ThemeDocument, text: string, successMessage: string): void {
+    this.activeThemeInternal.set(theme);
+    this.activeThemeTextInternal.set(text);
+    this.draftThemeInternal.set(theme);
+    this.draftTextInternal.set(text);
+    this.draftIsValidInternal.set(true);
+    this.draftErrorsInternal.set([]);
+    saveActiveThemeText(text);
+    saveDraftThemeText(text);
+    this.syncAnimationStylesheet();
+    this.setStatusMessage(successMessage);
+  }
+
+  private parseAndValidateTheme(text: string, label: string) {
+    try {
+      return validateThemeDocument(JSON.parse(text) as unknown);
+    } catch (error) {
+      return {
+        valid: false,
+        errors: [`${label} could not be parsed: ${error instanceof Error ? error.message : 'unknown JSON error'}`],
+        value: null
+      };
+    }
+  }
+
+  private buildTokenStyles(theme: ThemeDocument): Record<string, string> {
+    const styles: Record<string, string> = {};
+
+    for (const [tokenName, tokenValue] of Object.entries(theme.tokens.colors)) {
+      styles[`--${toKebabCase(tokenName)}`] = tokenValue;
+    }
+
+    for (const [tokenName, tokenValue] of Object.entries(theme.tokens.spacing)) {
+      styles[`--theme-spacing-${toKebabCase(tokenName)}`] = tokenValue;
+    }
+
+    for (const [tokenName, tokenValue] of Object.entries(theme.tokens.radii)) {
+      const cssVariableName = tokenName === 'radius'
+        ? '--radius'
+        : `--theme-radius-${toKebabCase(tokenName)}`;
+
+      styles[cssVariableName] = tokenValue;
+    }
+
+    for (const [tokenName, tokenValue] of Object.entries(theme.tokens.effects)) {
+      styles[`--theme-effect-${toKebabCase(tokenName)}`] = tokenValue;
+    }
+
+    return styles;
+  }
+
+  private syncAnimationStylesheet(): void {
+    const theme = this.activeThemeInternal();
+    const css = Object.entries(theme.animations)
+      .map(([className, definition]) => this.buildAnimationRule(className, definition))
+      .filter((rule) => rule.length > 0)
+      .join('\n\n');
+
+    if (!this.animationStyleElement) {
+      this.animationStyleElement = this.documentRef.createElement('style');
+      this.animationStyleElement.setAttribute('data-toju-theme-animations', 'true');
+      this.documentRef.head.appendChild(this.animationStyleElement);
+    }
+
+    this.animationStyleElement.textContent = css;
+  }
+
+  private buildAnimationRule(className: string, definition: ThemeAnimationDefinition): string {
+    const animationClass = `.${className}`;
+    const declarationLines = [
+      `animation-name: ${className};`,
+      `animation-duration: ${definition.duration ?? '240ms'};`,
+      `animation-timing-function: ${definition.easing ?? 'ease'};`,
+      `animation-delay: ${definition.delay ?? '0ms'};`,
+      `animation-iteration-count: ${definition.iterationCount ?? '1'};`,
+      `animation-fill-mode: ${definition.fillMode ?? 'both'};`,
+      `animation-direction: ${definition.direction ?? 'normal'};`
+    ];
+    const classRule = `${animationClass} {\n  ${declarationLines.join('\n  ')}\n}`;
+
+    if (!definition.keyframes || Object.keys(definition.keyframes).length === 0) {
+      return classRule;
+    }
+
+    const keyframeRule = `@keyframes ${className} {\n${Object.entries(definition.keyframes)
+      .map(([step, declarations]) => {
+        const lines = Object.entries(declarations)
+          .map(([property, value]) => `    ${toKebabCase(property)}: ${value};`)
+          .join('\n');
+
+        return `  ${step} {\n${lines}\n  }`;
+      })
+      .join('\n')}\n}`;
+
+    return `${keyframeRule}\n\n${classRule}`;
+  }
+
+  private setStatusMessage(message: string): void {
+    this.statusMessageInternal.set(message);
+
+    if (this.statusTimeoutId) {
+      clearTimeout(this.statusTimeoutId);
+    }
+
+    this.statusTimeoutId = setTimeout(() => {
+      this.statusMessageInternal.set(null);
+      this.statusTimeoutId = null;
+    }, 5000);
+  }
+}
\ No newline at end of file
diff --git a/toju-app/src/app/domains/theme/domain/theme-llm-guide.ts b/toju-app/src/app/domains/theme/domain/theme-llm-guide.ts
new file mode 100644
index 0000000..6bef479
--- /dev/null
+++ b/toju-app/src/app/domains/theme/domain/theme-llm-guide.ts
@@ -0,0 +1,171 @@
+import { DEFAULT_THEME_DOCUMENT } from './theme.defaults';
+import {
+  THEME_LAYOUT_CONTAINERS,
+  THEME_REGISTRY
+} from './theme.registry';
+import {
+  THEME_ANIMATION_FIELDS,
+  THEME_ELEMENT_STYLE_FIELDS,
+  createAnimationStarterDefinition
+} from './theme.schema';
+
+function formatExample(example: string | number): string {
+  return typeof example === 'number'
+    ? `${example}`
+    : JSON.stringify(example);
+}
+
+function getLayoutKeysForContainer(containerKey: string): string[] {
+  return THEME_REGISTRY
+    .filter((entry) => entry.container === containerKey && entry.layoutEditable)
+    .map((entry) => entry.key);
+}
+
+function describeCapabilities(entry: (typeof THEME_REGISTRY)[number]): string {
+  const capabilities = [
+    entry.layoutEditable ? 'layout' : null,
+    entry.supportsTextOverride ? 'textOverride' : null,
+    entry.supportsLink ? 'link' : null,
+    entry.supportsIcon ? 'icon' : null
+  ].filter((value): value is string => value !== null);
+
+  return capabilities.length > 0
+    ? capabilities.join(', ')
+    : 'visual style overrides only';
+}
+
+const colorTokenKeys = Object.keys(DEFAULT_THEME_DOCUMENT.tokens.colors);
+const radiusTokenKeys = Object.keys(DEFAULT_THEME_DOCUMENT.tokens.radii);
+const effectTokenKeys = Object.keys(DEFAULT_THEME_DOCUMENT.tokens.effects);
+const layoutEditableKeys = THEME_REGISTRY
+  .filter((entry) => entry.layoutEditable)
+  .map((entry) => entry.key);
+const guideTemplateDocument = {
+  meta: {
+    name: 'Theme Name',
+    version: '1.0.0',
+    description: 'Short mood and material direction.'
+  },
+  tokens: {
+    colors: {
+      background: '224 28% 7%',
+      foreground: '210 40% 96%',
+      primary: '193 95% 68%',
+      panelBackground: '224 24% 11%',
+      titleBarBackground: '226 34% 7%'
+    },
+    spacing: {},
+    radii: {
+      radius: '0.875rem',
+      surface: '1.35rem'
+    },
+    effects: {
+      glassBlur: 'blur(18px) saturate(135%)'
+    }
+  },
+  layout: {
+    chatRoomMainPanel: {
+      container: 'roomLayout',
+      grid: {
+        x: 4,
+        y: 0,
+        w: 12,
+        h: 12
+      }
+    }
+  },
+  elements: {
+    titleBar: {
+      backgroundColor: 'hsl(var(--title-bar-background) / 0.82)',
+      color: 'hsl(var(--foreground))',
+      border: '1px solid hsl(var(--border) / 0.72)',
+      backdropFilter: 'var(--theme-effect-glass-blur)'
+    },
+    chatRoomMainPanel: {
+      backgroundColor: 'hsl(var(--panel-background) / 0.82)',
+      borderRadius: 'var(--theme-radius-surface)',
+      boxShadow: 'var(--theme-effect-panel-shadow)'
+    }
+  },
+  animations: {
+    'theme-fade-in': createAnimationStarterDefinition()
+  }
+};
+
+export const THEME_LLM_GUIDE = [
+  'TOJU THEME CREATION SHEET FOR LLMS',
+  '',
+  'Goal',
+  '- Produce one valid JSON theme document for Toju Theme Studio.',
+  '- Return JSON only when asked to generate a theme. Do not wrap the result in Markdown fences or add commentary.',
+  '',
+  'Core rules',
+  '- Keep the top-level keys exactly: meta, tokens, layout, elements, animations.',
+  '- Use strict JSON with double-quoted keys, no comments, and no trailing commas.',
+  '- Omitted optional keys inherit from the built-in default theme, so leave out anything you are not intentionally changing.',
+  '- Do not invent new top-level sections, layout containers, or element style properties.',
+  '- links must be absolute http or https URLs.',
+  '- animationClass must be a safe CSS class token and should match an entry in animations or an existing class already shipped by the app.',
+  '- layout.grid values must be integers. x and y are zero-based. w and h must be greater than 0.',
+  '- opacity must be a number between 0 and 1.',
+  '',
+  'Theme creation workflow',
+  '- 1. Set meta.name, meta.version, and an optional meta.description.',
+  '- 2. Define the palette and tokens first. Prefer token-driven colors instead of hard-coded values in every element.',
+  '- 3. Move only layout-editable surfaces in layout.',
+  '- 4. Add visual overrides in elements using the supported style fields below.',
+  '- 5. Add animations only when an element actually references them with animationClass.',
+  '',
+  'Token rules',
+  '- tokens.colors entries become CSS variables like --background or --surface-highlight-alt.',
+  '- Color token values should usually be raw HSL channels such as "224 28% 7%". The shell wraps many built-in color tokens with hsl(var(--token)).',
+  '- You may add extra color tokens if you also reference them with CSS variables in element overrides.',
+  '- tokens.spacing entries become --theme-spacing-<kebab-case-key>.',
+  '- tokens.radii.radius maps to --radius. Other radius keys become --theme-radius-<kebab-case-key>.',
+  '- tokens.effects entries become --theme-effect-<kebab-case-key>.',
+  `- Built-in shell color tokens: ${colorTokenKeys.join(', ')}.`,
+  `- Built-in shell radius tokens: ${radiusTokenKeys.join(', ')}.`,
+  `- Built-in shell effect tokens: ${effectTokenKeys.join(', ')}.`,
+  '',
+  'Top-level schema reference',
+  '- meta: { name: string, version: string, description?: string }',
+  '- tokens: { colors: Record<string, string>, spacing: Record<string, string>, radii: Record<string, string>, effects: Record<string, string> }',
+  '- layout: Record<string, { container: "appShell" | "roomLayout", grid: { x: number, y: number, w: number, h: number } }>',
+  '- elements: Record<string, ThemeElementStyles>',
+  '- animations: Record<string, { duration?, easing?, delay?, iterationCount?, fillMode?, direction?, keyframes? }>',
+  '',
+  'Layout containers',
+  ...THEME_LAYOUT_CONTAINERS.map((container) => {
+    const layoutKeys = getLayoutKeysForContainer(container.key);
+
+    return `- ${container.key}: ${container.columns} columns x ${container.rows} rows. ${container.description} Layout keys: ${layoutKeys.join(', ')}.`;
+  }),
+  `- Only these keys should normally appear in layout: ${layoutEditableKeys.join(', ')}.`,
+  '',
+  'Registered theme element keys',
+  ...THEME_REGISTRY.map((entry) => {
+    const container = entry.container ?? 'none';
+
+    return `- ${entry.key}: ${entry.label}. Category=${entry.category}. Container=${container}. ${entry.description} Supported extras: ${describeCapabilities(entry)}.`;
+  }),
+  '',
+  'Supported element style fields',
+  ...THEME_ELEMENT_STYLE_FIELDS.map((field) => {
+    return `- ${field.key}: ${field.description} Example: ${formatExample(field.example)}.`;
+  }),
+  '',
+  'Supported animation fields',
+  ...THEME_ANIMATION_FIELDS.map((field) => {
+    return `- ${field.key}: ${field.description} Example: ${formatExample(field.example)}.`;
+  }),
+  '',
+  'Minimal valid starting point',
+  JSON.stringify(guideTemplateDocument, null, 2),
+  '',
+  'Output checklist',
+  '- Return one JSON object only.',
+  '- Prefer token references like hsl(var(--foreground)) and var(--theme-effect-glass-blur) inside element overrides.',
+  '- Keep layout edits plausible for the declared container grid size.',
+  '- If a field is unsupported, omit it instead of guessing.',
+  '- If a section does not need changes, leave it empty rather than filling it with noise.'
+].join('\n');
\ No newline at end of file
diff --git a/toju-app/src/app/domains/theme/domain/theme.defaults.ts b/toju-app/src/app/domains/theme/domain/theme.defaults.ts
new file mode 100644
index 0000000..a0dc64f
--- /dev/null
+++ b/toju-app/src/app/domains/theme/domain/theme.defaults.ts
@@ -0,0 +1,241 @@
+import {
+  ThemeDocument,
+  ThemeElementStyles,
+  ThemeLayoutEntry
+} from './theme.models';
+import {
+  THEME_LAYOUT_CONTAINERS,
+  THEME_REGISTRY,
+  getLayoutEditableThemeKeys
+} from './theme.registry';
+
+function createDefaultElements(): Record<string, ThemeElementStyles> {
+  return Object.fromEntries(
+    THEME_REGISTRY.map((entry) => [entry.key, {}])
+  ) as Record<string, ThemeElementStyles>;
+}
+
+function createDefaultLayout(): Record<string, ThemeLayoutEntry> {
+  const layoutEntries: Record<string, ThemeLayoutEntry> = {};
+
+  for (const key of getLayoutEditableThemeKeys()) {
+    if (key === 'serversRail') {
+      layoutEntries[key] = {
+        container: 'appShell',
+        grid: { x: 0,
+          y: 0,
+          w: 1,
+          h: 1 }
+      };
+      continue;
+    }
+
+    if (key === 'appWorkspace') {
+      const appShell = THEME_LAYOUT_CONTAINERS.find((container) => container.key === 'appShell');
+
+      layoutEntries[key] = {
+        container: 'appShell',
+        grid: { x: 1,
+          y: 0,
+          w: (appShell?.columns ?? 20) - 1,
+          h: 1 }
+      };
+      continue;
+    }
+
+    if (key === 'chatRoomChannelsPanel') {
+      layoutEntries[key] = {
+        container: 'roomLayout',
+        grid: { x: 0,
+          y: 0,
+          w: 4,
+          h: 12 }
+      };
+      continue;
+    }
+
+    if (key === 'chatRoomMainPanel') {
+      layoutEntries[key] = {
+        container: 'roomLayout',
+        grid: { x: 4,
+          y: 0,
+          w: 12,
+          h: 12 }
+      };
+      continue;
+    }
+
+    if (key === 'chatRoomMembersPanel') {
+      layoutEntries[key] = {
+        container: 'roomLayout',
+        grid: { x: 16,
+          y: 0,
+          w: 4,
+          h: 12 }
+      };
+    }
+  }
+
+  return layoutEntries;
+}
+
+function createDarkDefaultElements(): Record<string, ThemeElementStyles> {
+  const elements = createDefaultElements();
+
+  elements['appRoot'] = {
+    backgroundColor: 'hsl(var(--background))',
+    color: 'hsl(var(--foreground))',
+    gradient: 'radial-gradient(circle at top, hsl(var(--surface-highlight) / 0.18), transparent 34%), linear-gradient(180deg, rgba(5, 8, 15, 0.98), rgba(9, 12, 20, 1))'
+  };
+  elements['serversRail'] = {
+    backgroundColor: 'hsl(var(--rail-background) / 0.96)',
+    gradient: 'linear-gradient(180deg, rgba(10, 14, 25, 0.92), rgba(6, 9, 16, 0.98))',
+    boxShadow: 'inset -1px 0 0 hsl(var(--border) / 0.82), 18px 0 38px rgba(0, 0, 0, 0.22)',
+    backdropFilter: 'var(--theme-effect-glass-blur)'
+  };
+  elements['appWorkspace'] = {
+    backgroundColor: 'hsl(var(--workspace-background))',
+    gradient: 'radial-gradient(circle at top right, hsl(var(--surface-highlight-alt) / 0.14), transparent 30%), linear-gradient(180deg, rgba(9, 12, 21, 0.96), rgba(7, 10, 18, 1))'
+  };
+  elements['titleBar'] = {
+    backgroundColor: 'hsl(var(--title-bar-background) / 0.82)',
+    color: 'hsl(var(--foreground))',
+    gradient: 'linear-gradient(180deg, rgba(20, 26, 41, 0.52), rgba(7, 10, 18, 0.18))',
+    boxShadow: 'inset 0 -1px 0 hsl(var(--border) / 0.78), 0 12px 28px rgba(0, 0, 0, 0.18)',
+    backdropFilter: 'var(--theme-effect-glass-blur)'
+  };
+  elements['chatRoomChannelsPanel'] = {
+    backgroundColor: 'hsl(var(--panel-background) / 0.9)',
+    color: 'hsl(var(--foreground))',
+    border: '1px solid hsl(var(--border) / 0.7)',
+    borderRadius: 'var(--theme-radius-surface)',
+    gradient: 'linear-gradient(180deg, rgba(18, 24, 38, 0.82), rgba(10, 13, 23, 0.88))',
+    boxShadow: 'var(--theme-effect-soft-shadow)',
+    backdropFilter: 'var(--theme-effect-glass-blur)'
+  };
+  elements['chatRoomMainPanel'] = {
+    backgroundColor: 'hsl(var(--panel-background) / 0.82)',
+    color: 'hsl(var(--foreground))',
+    border: '1px solid hsl(var(--border) / 0.62)',
+    borderRadius: 'var(--theme-radius-surface)',
+    gradient: 'radial-gradient(circle at top, hsl(var(--surface-highlight) / 0.12), transparent 28%), linear-gradient(180deg, rgba(16, 20, 34, 0.82), rgba(8, 11, 19, 0.92))',
+    boxShadow: 'var(--theme-effect-panel-shadow)',
+    backdropFilter: 'var(--theme-effect-glass-blur)'
+  };
+  elements['chatRoomMembersPanel'] = {
+    backgroundColor: 'hsl(var(--panel-background-alt) / 0.92)',
+    color: 'hsl(var(--foreground))',
+    border: '1px solid hsl(var(--border) / 0.7)',
+    borderRadius: 'var(--theme-radius-surface)',
+    gradient: 'linear-gradient(180deg, rgba(22, 27, 41, 0.82), rgba(11, 14, 24, 0.9))',
+    boxShadow: 'var(--theme-effect-soft-shadow)',
+    backdropFilter: 'var(--theme-effect-glass-blur)'
+  };
+  elements['chatRoomEmptyState'] = {
+    backgroundColor: 'hsl(var(--panel-background-alt) / 0.88)',
+    color: 'hsl(var(--muted-foreground))',
+    border: '1px dashed hsl(var(--border) / 0.7)',
+    borderRadius: 'var(--theme-radius-surface)',
+    gradient: 'radial-gradient(circle at top, hsl(var(--surface-highlight) / 0.08), transparent 45%)',
+    boxShadow: 'var(--theme-effect-soft-shadow)'
+  };
+  elements['voiceWorkspace'] = {
+    backgroundColor: 'hsl(var(--panel-background) / 0.74)',
+    color: 'hsl(var(--foreground))',
+    border: '1px solid hsl(var(--border) / 0.62)',
+    borderRadius: 'calc(var(--theme-radius-surface) + 0.2rem)',
+    gradient: 'radial-gradient(circle at top right, hsl(var(--surface-highlight) / 0.14), transparent 32%), linear-gradient(180deg, rgba(18, 23, 37, 0.78), rgba(9, 12, 21, 0.88))',
+    boxShadow: 'var(--theme-effect-panel-shadow)',
+    backdropFilter: 'var(--theme-effect-glass-blur)'
+  };
+  elements['floatingVoiceControls'] = {
+    backgroundColor: 'hsl(var(--panel-background-alt) / 0.94)',
+    color: 'hsl(var(--foreground))',
+    border: '1px solid hsl(var(--border) / 0.78)',
+    borderRadius: 'var(--theme-radius-pill)',
+    gradient: 'linear-gradient(180deg, rgba(24, 31, 47, 0.92), rgba(13, 17, 29, 0.96))',
+    boxShadow: 'var(--theme-effect-soft-shadow)',
+    backdropFilter: 'var(--theme-effect-glass-blur)'
+  };
+
+  return elements;
+}
+
+function hasOnlyLegacyRadius(radii: Record<string, string>): boolean {
+  const keys = Object.keys(radii);
+
+  return keys.length === 1 && radii['radius'] === '0.375rem';
+}
+
+function allElementsEmpty(elements: Record<string, ThemeElementStyles>): boolean {
+  return Object.values(elements).every((elementStyles) => Object.keys(elementStyles).length === 0);
+}
+
+export function createDefaultThemeDocument(): ThemeDocument {
+  return {
+    meta: {
+      name: 'Toju Default Dark',
+      version: '2.0.0',
+      description: 'Built-in dark glass theme for the full Toju app shell.'
+    },
+    tokens: {
+      colors: {
+        background: '224 28% 7%',
+        foreground: '210 40% 96%',
+        card: '224 25% 10%',
+        cardForeground: '210 40% 96%',
+        popover: '224 26% 9%',
+        popoverForeground: '210 40% 96%',
+        primary: '193 95% 68%',
+        primaryForeground: '222 47% 11%',
+        secondary: '223 19% 16%',
+        secondaryForeground: '210 40% 96%',
+        muted: '223 18% 14%',
+        mutedForeground: '215 20% 70%',
+        accent: '218 22% 18%',
+        accentForeground: '210 40% 98%',
+        destructive: '0 72% 55%',
+        destructiveForeground: '0 0% 100%',
+        border: '222 18% 22%',
+        input: '222 18% 22%',
+        ring: '193 95% 68%',
+        railBackground: '226 33% 8%',
+        workspaceBackground: '224 30% 9%',
+        panelBackground: '224 24% 11%',
+        panelBackgroundAlt: '222 22% 13%',
+        titleBarBackground: '226 34% 7%',
+        surfaceHighlight: '193 95% 68%',
+        surfaceHighlightAlt: '261 82% 72%'
+      },
+      spacing: {},
+      radii: {
+        radius: '0.875rem',
+        surface: '1.35rem',
+        pill: '999px'
+      },
+      effects: {
+        panelShadow: '0 24px 60px rgba(0, 0, 0, 0.42)',
+        softShadow: '0 14px 36px rgba(0, 0, 0, 0.28)',
+        glassBlur: 'blur(18px) saturate(135%)'
+      }
+    },
+    layout: createDefaultLayout(),
+    elements: createDarkDefaultElements(),
+    animations: {}
+  };
+}
+
+export function isLegacyDefaultThemeDocument(document: ThemeDocument): boolean {
+  return document.meta.name === 'Toju Default Theme'
+    && document.meta.version === '1.0.0'
+    && document.meta.description === 'Safe baseline theme that matches the built-in Toju shell layout.'
+    && Object.keys(document.tokens.colors).length === 0
+    && Object.keys(document.tokens.spacing).length === 0
+    && hasOnlyLegacyRadius(document.tokens.radii)
+    && Object.keys(document.tokens.effects).length === 0
+    && allElementsEmpty(document.elements)
+    && Object.keys(document.animations).length === 0;
+}
+
+export const DEFAULT_THEME_DOCUMENT: ThemeDocument = createDefaultThemeDocument();
+export const DEFAULT_THEME_JSON = JSON.stringify(DEFAULT_THEME_DOCUMENT, null, 2);
\ No newline at end of file
diff --git a/toju-app/src/app/domains/theme/domain/theme.models.ts b/toju-app/src/app/domains/theme/domain/theme.models.ts
new file mode 100644
index 0000000..b65d1c5
--- /dev/null
+++ b/toju-app/src/app/domains/theme/domain/theme.models.ts
@@ -0,0 +1,133 @@
+export type ThemeContainerKey = 'appShell' | 'roomLayout';
+
+export interface ThemeMeta {
+  name: string;
+  version: string;
+  description?: string;
+}
+
+export interface ThemeTokenGroups {
+  colors: Record<string, string>;
+  spacing: Record<string, string>;
+  radii: Record<string, string>;
+  effects: Record<string, string>;
+}
+
+export interface ThemeGridRect {
+  x: number;
+  y: number;
+  w: number;
+  h: number;
+}
+
+export interface ThemeLayoutEntry {
+  container: ThemeContainerKey;
+  grid: ThemeGridRect;
+}
+
+export interface ThemeElementStyles {
+  width?: string;
+  height?: string;
+  minWidth?: string;
+  minHeight?: string;
+  maxWidth?: string;
+  maxHeight?: string;
+  position?: 'static' | 'relative' | 'absolute' | 'sticky';
+  top?: string;
+  right?: string;
+  bottom?: string;
+  left?: string;
+  opacity?: number;
+  padding?: string;
+  margin?: string;
+  border?: string;
+  borderRadius?: string;
+  backgroundColor?: string;
+  color?: string;
+  backgroundImage?: string;
+  backgroundSize?: string;
+  backgroundPosition?: string;
+  backgroundRepeat?: string;
+  gradient?: string;
+  boxShadow?: string;
+  backdropFilter?: string;
+  icon?: string;
+  textOverride?: string;
+  link?: string;
+  animationClass?: string;
+}
+
+export type ThemeElementStyleProperty = keyof ThemeElementStyles;
+
+export interface ThemeAnimationDefinition {
+  duration?: string;
+  easing?: string;
+  delay?: string;
+  iterationCount?: string;
+  fillMode?: 'none' | 'forwards' | 'backwards' | 'both';
+  direction?: 'normal' | 'reverse' | 'alternate' | 'alternate-reverse';
+  keyframes?: Record<string, Record<string, string | number>>;
+}
+
+export interface ThemeDocument {
+  meta: ThemeMeta;
+  tokens: ThemeTokenGroups;
+  layout: Record<string, ThemeLayoutEntry>;
+  elements: Record<string, ThemeElementStyles>;
+  animations: Record<string, ThemeAnimationDefinition>;
+}
+
+export interface ThemeLayoutContainerDefinition {
+  key: ThemeContainerKey;
+  label: string;
+  description: string;
+  columns: number;
+  rows: number;
+  templateColumns?: string;
+  templateRows?: string;
+}
+
+export interface ThemeRegistryEntry {
+  key: string;
+  label: string;
+  description: string;
+  category: 'shell' | 'room' | 'overlay' | 'state';
+  container?: ThemeContainerKey;
+  layoutEditable: boolean;
+  pickerVisible: boolean;
+  supportsTextOverride: boolean;
+  supportsLink: boolean;
+  supportsIcon: boolean;
+}
+
+export interface SavedThemeSummary {
+  description: string | null;
+  error: string | null;
+  fileName: string;
+  filePath: string;
+  isValid: boolean;
+  modifiedAt: number;
+  themeName: string;
+  version: string | null;
+}
+
+export interface ThemeValidationResult {
+  valid: boolean;
+  errors: string[];
+  value: ThemeDocument | null;
+}
+
+export interface ThemeGridEditorItem {
+  key: string;
+  label: string;
+  description: string;
+  grid: ThemeGridRect;
+}
+
+export interface ThemeSchemaField<T extends string = string> {
+  key: T;
+  description: string;
+  type: 'string' | 'number' | 'object';
+  example: string | number;
+  examples: readonly (string | number)[];
+}
\ No newline at end of file
diff --git a/toju-app/src/app/domains/theme/domain/theme.registry.ts b/toju-app/src/app/domains/theme/domain/theme.registry.ts
new file mode 100644
index 0000000..9a51b62
--- /dev/null
+++ b/toju-app/src/app/domains/theme/domain/theme.registry.ts
@@ -0,0 +1,161 @@
+import {
+  ThemeLayoutContainerDefinition,
+  ThemeRegistryEntry
+} from './theme.models';
+
+export const THEME_LAYOUT_CONTAINERS: readonly ThemeLayoutContainerDefinition[] = [
+  {
+    key: 'appShell',
+    label: 'App Shell',
+    description: 'Controls how the global rail and workspace split the application frame.',
+    columns: 20,
+    rows: 1,
+    templateColumns: '4rem repeat(19, minmax(0, 1fr))'
+  },
+  {
+    key: 'roomLayout',
+    label: 'Room Workspace',
+    description: 'Controls the channel list, main chat panel, and member list inside a room.',
+    columns: 20,
+    rows: 12,
+    templateColumns: 'repeat(4, 4.25rem) repeat(12, minmax(0, 1fr)) repeat(4, 4.25rem)'
+  }
+];
+
+export const THEME_REGISTRY: readonly ThemeRegistryEntry[] = [
+  {
+    key: 'appRoot',
+    label: 'App Root',
+    description: 'Global workspace wrapper that owns theme tokens and high-level app background styling.',
+    category: 'shell',
+    layoutEditable: false,
+    pickerVisible: false,
+    supportsTextOverride: false,
+    supportsLink: false,
+    supportsIcon: false
+  },
+  {
+    key: 'serversRail',
+    label: 'Servers Rail',
+    description: 'The persistent left navigation rail that holds saved servers and the create button.',
+    category: 'shell',
+    container: 'appShell',
+    layoutEditable: true,
+    pickerVisible: true,
+    supportsTextOverride: false,
+    supportsLink: false,
+    supportsIcon: false
+  },
+  {
+    key: 'appWorkspace',
+    label: 'App Workspace',
+    description: 'The main workspace area to the right of the server rail.',
+    category: 'shell',
+    container: 'appShell',
+    layoutEditable: true,
+    pickerVisible: true,
+    supportsTextOverride: false,
+    supportsLink: false,
+    supportsIcon: false
+  },
+  {
+    key: 'titleBar',
+    label: 'Title Bar',
+    description: 'The top application bar that shows the active room context and desktop controls.',
+    category: 'shell',
+    layoutEditable: false,
+    pickerVisible: true,
+    supportsTextOverride: true,
+    supportsLink: true,
+    supportsIcon: true
+  },
+  {
+    key: 'chatRoomChannelsPanel',
+    label: 'Channels Panel',
+    description: 'The room-side panel showing text and voice channels.',
+    category: 'room',
+    container: 'roomLayout',
+    layoutEditable: true,
+    pickerVisible: true,
+    supportsTextOverride: false,
+    supportsLink: false,
+    supportsIcon: false
+  },
+  {
+    key: 'chatRoomMainPanel',
+    label: 'Chat Panel',
+    description: 'The main room panel that hosts chat messages and the voice workspace overlay.',
+    category: 'room',
+    container: 'roomLayout',
+    layoutEditable: true,
+    pickerVisible: true,
+    supportsTextOverride: false,
+    supportsLink: false,
+    supportsIcon: false
+  },
+  {
+    key: 'chatRoomMembersPanel',
+    label: 'Members Panel',
+    description: 'The right-hand room panel showing online and offline members.',
+    category: 'room',
+    container: 'roomLayout',
+    layoutEditable: true,
+    pickerVisible: true,
+    supportsTextOverride: false,
+    supportsLink: false,
+    supportsIcon: false
+  },
+  {
+    key: 'chatRoomEmptyState',
+    label: 'Room Empty State',
+    description: 'The empty-state panel displayed when no room or no text channels are available.',
+    category: 'state',
+    layoutEditable: false,
+    pickerVisible: true,
+    supportsTextOverride: true,
+    supportsLink: true,
+    supportsIcon: true
+  },
+  {
+    key: 'voiceWorkspace',
+    label: 'Voice Workspace',
+    description: 'The stream-focused overlay and mini-window used when voice workspace is open.',
+    category: 'overlay',
+    layoutEditable: false,
+    pickerVisible: true,
+    supportsTextOverride: false,
+    supportsLink: false,
+    supportsIcon: false
+  },
+  {
+    key: 'floatingVoiceControls',
+    label: 'Floating Voice Controls',
+    description: 'The compact floating voice controls shown when the active voice server is off-screen.',
+    category: 'overlay',
+    layoutEditable: false,
+    pickerVisible: true,
+    supportsTextOverride: false,
+    supportsLink: false,
+    supportsIcon: false
+  }
+];
+
+export function findThemeRegistryEntry(key: string): ThemeRegistryEntry | null {
+  return THEME_REGISTRY.find((entry) => entry.key === key) ?? null;
+}
+
+export function findThemeLayoutContainer(key: string): ThemeLayoutContainerDefinition | null {
+  return THEME_LAYOUT_CONTAINERS.find((container) => container.key === key) ?? null;
+}
+
+export function getLayoutEditableThemeKeys(): string[] {
+  return THEME_REGISTRY
+    .filter((entry) => entry.layoutEditable)
+    .map((entry) => entry.key);
+}
+
+export function getPickerVisibleThemeKeys(): string[] {
+  return THEME_REGISTRY
+    .filter((entry) => entry.pickerVisible)
+    .map((entry) => entry.key);
+}
\ No newline at end of file
diff --git a/toju-app/src/app/domains/theme/domain/theme.schema.ts b/toju-app/src/app/domains/theme/domain/theme.schema.ts
new file mode 100644
index 0000000..6f1b44e
--- /dev/null
+++ b/toju-app/src/app/domains/theme/domain/theme.schema.ts
@@ -0,0 +1,432 @@
+import {
+  ThemeDocument,
+  ThemeElementStyleProperty,
+  ThemeSchemaField
+} from './theme.models';
+
+export const THEME_TOP_LEVEL_FIELDS: readonly ThemeSchemaField[] = [
+  {
+    key: 'meta',
+    description: 'Theme metadata used for naming, versioning, and describing the preset.',
+    type: 'object',
+    example: '{ "name": "Aurora" }',
+    examples: ['{ "name": "Aurora" }']
+  },
+  {
+    key: 'tokens',
+    description: 'Global CSS-variable token overrides for colors, spacing, radii, and effects.',
+    type: 'object',
+    example: '{ "colors": { "background": "220 18% 10%" } }',
+    examples: ['{ "colors": { "background": "220 18% 10%" } }']
+  },
+  {
+    key: 'layout',
+    description: 'Grid layout entries for registered moveable surfaces.',
+    type: 'object',
+    example: '{ "chatRoomMainPanel": { "container": "roomLayout", "grid": { "x": 4, "y": 0, "w": 12, "h": 12 } } }',
+    examples: ['{ "chatRoomMainPanel": { "container": "roomLayout", "grid": { "x": 4, "y": 0, "w": 12, "h": 12 } } }']
+  },
+  {
+    key: 'elements',
+    description: 'Per-element visual overrides such as color, spacing, links, icons, and text.',
+    type: 'object',
+    example: '{ "titleBar": { "backgroundColor": "rgba(7,11,20,0.84)" } }',
+    examples: ['{ "titleBar": { "backgroundColor": "rgba(7,11,20,0.84)" } }']
+  },
+  {
+    key: 'animations',
+    description: 'Animation class definitions keyed by class name. Entries can include timing and keyframes.',
+    type: 'object',
+    example: '{ "theme-fade-in": { "duration": "240ms" } }',
+    examples: ['{ "theme-fade-in": { "duration": "240ms" } }']
+  }
+];
+
+export const THEME_TOKEN_GROUP_FIELDS: readonly ThemeSchemaField[] = [
+  {
+    key: 'colors',
+    description: 'Maps token names such as background or primary to CSS variable values.',
+    type: 'object',
+    example: '{ "background": "220 18% 10%" }',
+    examples: ['{ "background": "220 18% 10%" }']
+  },
+  {
+    key: 'spacing',
+    description: 'Custom theme spacing variables exposed as --theme-spacing-* CSS variables.',
+    type: 'object',
+    example: '{ "panelGap": "12px" }',
+    examples: ['{ "panelGap": "12px" }']
+  },
+  {
+    key: 'radii',
+    description: 'Theme radius variables exposed as --radius or --theme-radius-* CSS variables.',
+    type: 'object',
+    example: '{ "radius": "18px" }',
+    examples: ['{ "radius": "18px" }']
+  },
+  {
+    key: 'effects',
+    description: 'Custom effect variables exposed as --theme-effect-* CSS variables.',
+    type: 'object',
+    example: '{ "glassBlur": "18px" }',
+    examples: ['{ "glassBlur": "18px" }']
+  }
+];
+
+export const THEME_LAYOUT_FIELDS: readonly ThemeSchemaField[] = [
+  {
+    key: 'container',
+    description: 'The registered layout container that owns this grid item.',
+    type: 'string',
+    example: 'roomLayout',
+    examples: ['appShell', 'roomLayout']
+  },
+  {
+    key: 'grid',
+    description: 'Grid coordinates for the item within its container.',
+    type: 'object',
+    example: '{ "x": 4, "y": 0, "w": 12, "h": 12 }',
+    examples: ['{ "x": 4, "y": 0, "w": 12, "h": 12 }']
+  }
+];
+
+export const THEME_GRID_FIELDS: readonly ThemeSchemaField[] = [
+  {
+    key: 'x',
+    description: 'Horizontal grid start column, zero-based.',
+    type: 'number',
+    example: 4,
+    examples: [0, 1, 4]
+  },
+  {
+    key: 'y',
+    description: 'Vertical grid start row, zero-based.',
+    type: 'number',
+    example: 0,
+    examples: [0, 1, 6]
+  },
+  {
+    key: 'w',
+    description: 'Grid width in columns.',
+    type: 'number',
+    example: 12,
+    examples: [1, 4, 12]
+  },
+  {
+    key: 'h',
+    description: 'Grid height in rows.',
+    type: 'number',
+    example: 12,
+    examples: [1, 4, 12]
+  }
+];
+
+export const THEME_ANIMATION_FIELDS: readonly ThemeSchemaField[] = [
+  {
+    key: 'duration',
+    description: 'Animation duration.',
+    type: 'string',
+    example: '240ms',
+    examples: ['200ms', '240ms', '600ms']
+  },
+  {
+    key: 'easing',
+    description: 'Animation easing function.',
+    type: 'string',
+    example: 'ease-out',
+    examples: ['ease', 'ease-out', 'cubic-bezier(0.16, 1, 0.3, 1)']
+  },
+  {
+    key: 'delay',
+    description: 'Optional animation delay.',
+    type: 'string',
+    example: '0ms',
+    examples: ['0ms', '120ms']
+  },
+  {
+    key: 'iterationCount',
+    description: 'How many times the animation should run.',
+    type: 'string',
+    example: '1',
+    examples: ['1', 'infinite']
+  },
+  {
+    key: 'fillMode',
+    description: 'Animation fill behavior after running.',
+    type: 'string',
+    example: 'both',
+    examples: ['none', 'forwards', 'backwards', 'both']
+  },
+  {
+    key: 'direction',
+    description: 'Animation direction.',
+    type: 'string',
+    example: 'normal',
+    examples: ['normal', 'reverse', 'alternate']
+  },
+  {
+    key: 'keyframes',
+    description: 'Optional keyframe map keyed by from, to, or percentages.',
+    type: 'object',
+    example: '{ "0%": { "opacity": "0" }, "100%": { "opacity": "1" } }',
+    examples: ['{ "0%": { "opacity": "0" }, "100%": { "opacity": "1" } }']
+  }
+];
+
+export const THEME_ELEMENT_STYLE_FIELDS: readonly ThemeSchemaField<ThemeElementStyleProperty>[] = [
+  {
+    key: 'width',
+    description: 'CSS width applied to the selected element host.',
+    type: 'string',
+    example: '280px',
+    examples: ['280px', '20rem', 'min(24rem, 30vw)']
+  },
+  {
+    key: 'height',
+    description: 'CSS height applied to the selected element host.',
+    type: 'string',
+    example: '100%',
+    examples: ['100%', '22rem', 'calc(100vh - 4rem)']
+  },
+  {
+    key: 'minWidth',
+    description: 'CSS minimum width for the element host.',
+    type: 'string',
+    example: '16rem',
+    examples: ['16rem', '240px']
+  },
+  {
+    key: 'minHeight',
+    description: 'CSS minimum height for the element host.',
+    type: 'string',
+    example: '14rem',
+    examples: ['14rem', '200px']
+  },
+  {
+    key: 'maxWidth',
+    description: 'CSS maximum width for the element host.',
+    type: 'string',
+    example: '34rem',
+    examples: ['34rem', '80vw']
+  },
+  {
+    key: 'maxHeight',
+    description: 'CSS maximum height for the element host.',
+    type: 'string',
+    example: '90vh',
+    examples: ['90vh', '48rem']
+  },
+  {
+    key: 'position',
+    description: 'CSS positioning mode for the host element.',
+    type: 'string',
+    example: 'relative',
+    examples: ['static', 'relative', 'absolute', 'sticky']
+  },
+  {
+    key: 'top',
+    description: 'CSS top inset used with positioned elements.',
+    type: 'string',
+    example: '12px',
+    examples: ['0', '12px', '2rem']
+  },
+  {
+    key: 'right',
+    description: 'CSS right inset used with positioned elements.',
+    type: 'string',
+    example: '12px',
+    examples: ['0', '12px', '2rem']
+  },
+  {
+    key: 'bottom',
+    description: 'CSS bottom inset used with positioned elements.',
+    type: 'string',
+    example: '12px',
+    examples: ['0', '12px', '2rem']
+  },
+  {
+    key: 'left',
+    description: 'CSS left inset used with positioned elements.',
+    type: 'string',
+    example: '12px',
+    examples: ['0', '12px', '2rem']
+  },
+  {
+    key: 'opacity',
+    description: 'Element opacity between 0 and 1.',
+    type: 'number',
+    example: 0.96,
+    examples: [0.72, 0.88, 1]
+  },
+  {
+    key: 'padding',
+    description: 'CSS padding shorthand for internal spacing.',
+    type: 'string',
+    example: '12px',
+    examples: ['12px', '12px 16px', '1rem 1.25rem']
+  },
+  {
+    key: 'margin',
+    description: 'CSS margin shorthand for external spacing.',
+    type: 'string',
+    example: '0',
+    examples: ['0', '12px', '0 0 12px']
+  },
+  {
+    key: 'border',
+    description: 'CSS border shorthand.',
+    type: 'string',
+    example: '1px solid rgba(255,255,255,0.08)',
+    examples: ['1px solid rgba(255,255,255,0.08)', '0']
+  },
+  {
+    key: 'borderRadius',
+    description: 'CSS border radius shorthand.',
+    type: 'string',
+    example: '16px',
+    examples: ['12px', '16px', '999px']
+  },
+  {
+    key: 'backgroundColor',
+    description: 'CSS background-color value.',
+    type: 'string',
+    example: 'rgba(12, 18, 28, 0.88)',
+    examples: ['rgba(12, 18, 28, 0.88)', 'hsl(var(--card))']
+  },
+  {
+    key: 'color',
+    description: 'CSS text color value.',
+    type: 'string',
+    example: 'hsl(var(--foreground))',
+    examples: ['hsl(var(--foreground))', '#e8edf4']
+  },
+  {
+    key: 'backgroundImage',
+    description: 'CSS background image or image URL.',
+    type: 'string',
+    example: "url('/assets/themes/paper-noise.png')",
+    examples: ["url('/assets/themes/paper-noise.png')", "url('https://example.com/bg.jpg')"]
+  },
+  {
+    key: 'backgroundSize',
+    description: 'CSS background-size value.',
+    type: 'string',
+    example: 'cover',
+    examples: ['cover', 'contain', 'auto 100%']
+  },
+  {
+    key: 'backgroundPosition',
+    description: 'CSS background-position value.',
+    type: 'string',
+    example: 'center',
+    examples: ['center', 'top left', '50% 20%']
+  },
+  {
+    key: 'backgroundRepeat',
+    description: 'CSS background-repeat value.',
+    type: 'string',
+    example: 'no-repeat',
+    examples: ['no-repeat', 'repeat', 'repeat-x']
+  },
+  {
+    key: 'gradient',
+    description: 'CSS gradient layered above any background image.',
+    type: 'string',
+    example: 'linear-gradient(180deg, rgba(0,0,0,0.12), rgba(0,0,0,0.72))',
+    examples: ['linear-gradient(180deg, rgba(0,0,0,0.12), rgba(0,0,0,0.72))', 'radial-gradient(circle at top, rgba(255,255,255,0.12), transparent 60%)']
+  },
+  {
+    key: 'boxShadow',
+    description: 'CSS box-shadow value.',
+    type: 'string',
+    example: '0 18px 45px rgba(0,0,0,0.24)',
+    examples: ['0 18px 45px rgba(0,0,0,0.24)', 'none']
+  },
+  {
+    key: 'backdropFilter',
+    description: 'CSS backdrop-filter value.',
+    type: 'string',
+    example: 'blur(18px)',
+    examples: ['blur(18px)', 'saturate(140%) blur(12px)']
+  },
+  {
+    key: 'icon',
+    description: 'Optional theme icon string or image URL used by supported elements.',
+    type: 'string',
+    example: "url('/assets/themes/orb.svg')",
+    examples: ["url('/assets/themes/orb.svg')", 'TX']
+  },
+  {
+    key: 'textOverride',
+    description: 'Replacement text for supported elements.',
+    type: 'string',
+    example: 'Studio Mode',
+    examples: ['Studio Mode', 'Open to your crew']
+  },
+  {
+    key: 'link',
+    description: 'Safe http or https URL opened externally when supported elements are clicked.',
+    type: 'string',
+    example: 'https://example.com',
+    examples: ['https://example.com', 'https://toju.app/themes']
+  },
+  {
+    key: 'animationClass',
+    description: 'Animation class name defined in the animations section or in app CSS.',
+    type: 'string',
+    example: 'theme-fade-in',
+    examples: ['theme-fade-in', 'theme-glide-in']
+  }
+];
+
+export const THEME_SCHEMA = {
+  topLevel: THEME_TOP_LEVEL_FIELDS,
+  tokens: THEME_TOKEN_GROUP_FIELDS,
+  layout: THEME_LAYOUT_FIELDS,
+  grid: THEME_GRID_FIELDS,
+  animation: THEME_ANIMATION_FIELDS,
+  elementStyle: THEME_ELEMENT_STYLE_FIELDS
+} as const;
+
+export function findThemeElementStyleField(field: string): ThemeSchemaField<ThemeElementStyleProperty> | null {
+  return THEME_ELEMENT_STYLE_FIELDS.find((entry) => entry.key === field) ?? null;
+}
+
+export function getSuggestedValueOptions(
+  field: ThemeElementStyleProperty | string,
+  animationKeys: readonly string[] = []
+): readonly (string | number)[] {
+  if (field === 'animationClass' && animationKeys.length > 0) {
+    return animationKeys;
+  }
+
+  return findThemeElementStyleField(field)?.examples ?? [];
+}
+
+export function getSuggestedFieldDefault(
+  field: ThemeElementStyleProperty,
+  animationKeys: readonly string[] = []
+): string | number {
+  return getSuggestedValueOptions(field, animationKeys)[0] ?? '';
+}
+
+export function createAnimationStarterDefinition(): ThemeDocument['animations'][string] {
+  return {
+    duration: '240ms',
+    easing: 'ease-out',
+    delay: '0ms',
+    iterationCount: '1',
+    fillMode: 'both',
+    direction: 'normal',
+    keyframes: {
+      '0%': {
+        opacity: '0',
+        transform: 'translateY(10px)'
+      },
+      '100%': {
+        opacity: '1',
+        transform: 'translateY(0)'
+      }
+    }
+  };
+}
\ No newline at end of file
diff --git a/toju-app/src/app/domains/theme/domain/theme.validation.ts b/toju-app/src/app/domains/theme/domain/theme.validation.ts
new file mode 100644
index 0000000..95b5480
--- /dev/null
+++ b/toju-app/src/app/domains/theme/domain/theme.validation.ts
@@ -0,0 +1,452 @@
+import {
+  ThemeAnimationDefinition,
+  ThemeDocument,
+  ThemeElementStyleProperty,
+  ThemeElementStyles,
+  ThemeValidationResult
+} from './theme.models';
+import { createDefaultThemeDocument } from './theme.defaults';
+import {
+  THEME_LAYOUT_CONTAINERS,
+  THEME_REGISTRY,
+  getLayoutEditableThemeKeys
+} from './theme.registry';
+
+const TOP_LEVEL_KEYS = ['meta', 'tokens', 'layout', 'elements', 'animations'] as const;
+const META_KEYS = ['name', 'version', 'description'] as const;
+const TOKEN_GROUP_KEYS = ['colors', 'spacing', 'radii', 'effects'] as const;
+const LAYOUT_ENTRY_KEYS = ['container', 'grid'] as const;
+const GRID_KEYS = ['x', 'y', 'w', 'h'] as const;
+const ANIMATION_KEYS = ['duration', 'easing', 'delay', 'iterationCount', 'fillMode', 'direction', 'keyframes'] as const;
+const POSITION_VALUES = ['static', 'relative', 'absolute', 'sticky'] as const;
+const FILL_MODE_VALUES = ['none', 'forwards', 'backwards', 'both'] as const;
+const DIRECTION_VALUES = ['normal', 'reverse', 'alternate', 'alternate-reverse'] as const;
+const SAFE_LINK_PROTOCOLS = ['http:', 'https:'] as const;
+const SAFE_CLASS_PATTERN = /^[A-Za-z_][A-Za-z0-9_-]*$/;
+const KEYFRAME_STEP_PATTERN = /^(from|to|(?:\d|[1-9]\d|100)%)$/;
+const ELEMENT_STYLE_KEYS: readonly ThemeElementStyleProperty[] = [
+  'width',
+  'height',
+  'minWidth',
+  'minHeight',
+  'maxWidth',
+  'maxHeight',
+  'position',
+  'top',
+  'right',
+  'bottom',
+  'left',
+  'opacity',
+  'padding',
+  'margin',
+  'border',
+  'borderRadius',
+  'backgroundColor',
+  'color',
+  'backgroundImage',
+  'backgroundSize',
+  'backgroundPosition',
+  'backgroundRepeat',
+  'gradient',
+  'boxShadow',
+  'backdropFilter',
+  'icon',
+  'textOverride',
+  'link',
+  'animationClass'
+];
+
+function isPlainObject(value: unknown): value is Record<string, unknown> {
+  return !!value && typeof value === 'object' && !Array.isArray(value);
+}
+
+function validateUnknownKeys(
+  value: Record<string, unknown>,
+  allowedKeys: readonly string[],
+  path: string,
+  errors: string[]
+): void {
+  for (const key of Object.keys(value)) {
+    if (!allowedKeys.includes(key)) {
+      errors.push(`${path}.${key} is not part of the supported theme schema.`);
+    }
+  }
+}
+
+function validateString(value: unknown, path: string, errors: string[], allowEmpty = false): value is string {
+  if (typeof value !== 'string') {
+    errors.push(`${path} must be a string.`);
+    return false;
+  }
+
+  if (!allowEmpty && value.trim().length === 0) {
+    errors.push(`${path} cannot be empty.`);
+    return false;
+  }
+
+  return true;
+}
+
+function validateEnum<T extends readonly string[]>(
+  value: unknown,
+  allowedValues: T,
+  path: string,
+  errors: string[]
+): value is T[number] {
+  if (typeof value !== 'string' || !allowedValues.includes(value)) {
+    errors.push(`${path} must be one of: ${allowedValues.join(', ')}.`);
+    return false;
+  }
+
+  return true;
+}
+
+function validateInteger(
+  value: unknown,
+  path: string,
+  errors: string[],
+  minimum: number,
+  allowZero: boolean
+): value is number {
+  if (typeof value !== 'number' || !Number.isInteger(value)) {
+    errors.push(`${path} must be an integer.`);
+    return false;
+  }
+
+  if ((allowZero && value < minimum) || (!allowZero && value <= minimum)) {
+    errors.push(`${path} must be ${allowZero ? 'greater than or equal to' : 'greater than'} ${minimum}.`);
+    return false;
+  }
+
+  return true;
+}
+
+function validateNumberRange(
+  value: unknown,
+  path: string,
+  errors: string[],
+  minimum: number,
+  maximum: number
+): value is number {
+  if (typeof value !== 'number' || Number.isNaN(value)) {
+    errors.push(`${path} must be a number.`);
+    return false;
+  }
+
+  if (value < minimum || value > maximum) {
+    errors.push(`${path} must be between ${minimum} and ${maximum}.`);
+    return false;
+  }
+
+  return true;
+}
+
+function validateStringRecord(value: unknown, path: string, errors: string[]): value is Record<string, string> {
+  if (!isPlainObject(value)) {
+    errors.push(`${path} must be an object containing string values.`);
+    return false;
+  }
+
+  for (const [key, recordValue] of Object.entries(value)) {
+    validateString(recordValue, `${path}.${key}`, errors);
+  }
+
+  return true;
+}
+
+function validateElementStyles(value: unknown, path: string, errors: string[]): value is ThemeElementStyles {
+  if (!isPlainObject(value)) {
+    errors.push(`${path} must be an object.`);
+    return false;
+  }
+
+  validateUnknownKeys(value, ELEMENT_STYLE_KEYS, path, errors);
+
+  for (const [key, fieldValue] of Object.entries(value)) {
+    if (key === 'opacity') {
+      validateNumberRange(fieldValue, `${path}.${key}`, errors, 0, 1);
+      continue;
+    }
+
+    if (key === 'position') {
+      validateEnum(fieldValue, POSITION_VALUES, `${path}.${key}`, errors);
+      continue;
+    }
+
+    if (key === 'link') {
+      if (validateString(fieldValue, `${path}.${key}`, errors)) {
+        try {
+          const parsedUrl = new URL(fieldValue);
+
+          if (!SAFE_LINK_PROTOCOLS.includes(parsedUrl.protocol as (typeof SAFE_LINK_PROTOCOLS)[number])) {
+            errors.push(`${path}.${key} must use http or https.`);
+          }
+        } catch {
+          errors.push(`${path}.${key} must be a valid absolute URL.`);
+        }
+      }
+      continue;
+    }
+
+    if (key === 'animationClass') {
+      if (validateString(fieldValue, `${path}.${key}`, errors) && !SAFE_CLASS_PATTERN.test(fieldValue)) {
+        errors.push(`${path}.${key} must be a safe CSS class token.`);
+      }
+      continue;
+    }
+
+    validateString(fieldValue, `${path}.${key}`, errors, key === 'backgroundImage' || key === 'gradient');
+  }
+
+  return true;
+}
+
+function validateAnimationDefinition(value: unknown, path: string, errors: string[]): value is ThemeAnimationDefinition {
+  if (!isPlainObject(value)) {
+    errors.push(`${path} must be an object.`);
+    return false;
+  }
+
+  validateUnknownKeys(value, ANIMATION_KEYS, path, errors);
+
+  if (value['duration'] !== undefined) {
+    validateString(value['duration'], `${path}.duration`, errors);
+  }
+
+  if (value['easing'] !== undefined) {
+    validateString(value['easing'], `${path}.easing`, errors);
+  }
+
+  if (value['delay'] !== undefined) {
+    validateString(value['delay'], `${path}.delay`, errors);
+  }
+
+  if (value['iterationCount'] !== undefined) {
+    validateString(value['iterationCount'], `${path}.iterationCount`, errors);
+  }
+
+  if (value['fillMode'] !== undefined) {
+    validateEnum(value['fillMode'], FILL_MODE_VALUES, `${path}.fillMode`, errors);
+  }
+
+  if (value['direction'] !== undefined) {
+    validateEnum(value['direction'], DIRECTION_VALUES, `${path}.direction`, errors);
+  }
+
+  if (value['keyframes'] !== undefined) {
+    if (!isPlainObject(value['keyframes'])) {
+      errors.push(`${path}.keyframes must be an object.`);
+    } else {
+      for (const [step, declarations] of Object.entries(value['keyframes'])) {
+        if (!KEYFRAME_STEP_PATTERN.test(step)) {
+          errors.push(`${path}.keyframes.${step} is not a supported keyframe step.`);
+          continue;
+        }
+
+        if (!isPlainObject(declarations)) {
+          errors.push(`${path}.keyframes.${step} must be an object of CSS declarations.`);
+          continue;
+        }
+
+        for (const [cssProperty, cssValue] of Object.entries(declarations)) {
+          if (typeof cssValue !== 'string' && typeof cssValue !== 'number') {
+            errors.push(`${path}.keyframes.${step}.${cssProperty} must be a string or number.`);
+          }
+        }
+      }
+    }
+  }
+
+  return true;
+}
+
+function normaliseThemeDocument(input: Partial<ThemeDocument>): ThemeDocument {
+  const document = createDefaultThemeDocument();
+
+  document.meta = {
+    ...document.meta,
+    ...input.meta
+  };
+
+  document.tokens = {
+    colors: {
+      ...document.tokens.colors,
+      ...(input.tokens?.colors ?? {})
+    },
+    spacing: {
+      ...document.tokens.spacing,
+      ...(input.tokens?.spacing ?? {})
+    },
+    radii: {
+      ...document.tokens.radii,
+      ...(input.tokens?.radii ?? {})
+    },
+    effects: {
+      ...document.tokens.effects,
+      ...(input.tokens?.effects ?? {})
+    }
+  };
+
+  document.layout = {
+    ...document.layout,
+    ...(input.layout ?? {})
+  };
+
+  document.elements = {
+    ...document.elements,
+    ...(input.elements ?? {})
+  };
+
+  document.animations = {
+    ...document.animations,
+    ...(input.animations ?? {})
+  };
+
+  return document;
+}
+
+export function validateThemeDocument(input: unknown): ThemeValidationResult {
+  const errors: string[] = [];
+
+  if (!isPlainObject(input)) {
+    return {
+      valid: false,
+      errors: ['Theme document must be a JSON object.'],
+      value: null
+    };
+  }
+
+  validateUnknownKeys(input, TOP_LEVEL_KEYS, 'theme', errors);
+
+  const meta = input['meta'];
+
+  if (!isPlainObject(meta)) {
+    errors.push('theme.meta must be an object.');
+  } else {
+    validateUnknownKeys(meta, META_KEYS, 'theme.meta', errors);
+    validateString(meta['name'], 'theme.meta.name', errors);
+    validateString(meta['version'], 'theme.meta.version', errors);
+
+    if (meta['description'] !== undefined) {
+      validateString(meta['description'], 'theme.meta.description', errors, true);
+    }
+  }
+
+  const tokens = input['tokens'];
+
+  if (tokens !== undefined) {
+    if (!isPlainObject(tokens)) {
+      errors.push('theme.tokens must be an object.');
+    } else {
+      validateUnknownKeys(tokens, TOKEN_GROUP_KEYS, 'theme.tokens', errors);
+
+      if (tokens['colors'] !== undefined) {
+        validateStringRecord(tokens['colors'], 'theme.tokens.colors', errors);
+      }
+
+      if (tokens['spacing'] !== undefined) {
+        validateStringRecord(tokens['spacing'], 'theme.tokens.spacing', errors);
+      }
+
+      if (tokens['radii'] !== undefined) {
+        validateStringRecord(tokens['radii'], 'theme.tokens.radii', errors);
+      }
+
+      if (tokens['effects'] !== undefined) {
+        validateStringRecord(tokens['effects'], 'theme.tokens.effects', errors);
+      }
+    }
+  }
+
+  const layout = input['layout'];
+
+  if (layout !== undefined) {
+    if (!isPlainObject(layout)) {
+      errors.push('theme.layout must be an object.');
+    } else {
+      const allowedLayoutKeys = getLayoutEditableThemeKeys();
+
+      validateUnknownKeys(layout, allowedLayoutKeys, 'theme.layout', errors);
+
+      for (const [key, value] of Object.entries(layout)) {
+        const basePath = `theme.layout.${key}`;
+
+        if (!isPlainObject(value)) {
+          errors.push(`${basePath} must be an object.`);
+          continue;
+        }
+
+        validateUnknownKeys(value, LAYOUT_ENTRY_KEYS, basePath, errors);
+
+        if (value['container'] !== undefined) {
+          validateEnum(
+            value['container'],
+            THEME_LAYOUT_CONTAINERS.map((container) => container.key) as unknown as readonly string[],
+            `${basePath}.container`,
+            errors
+          );
+        }
+
+        const grid = value['grid'];
+
+        if (!isPlainObject(grid)) {
+          errors.push(`${basePath}.grid must be an object.`);
+          continue;
+        }
+
+        validateUnknownKeys(grid, GRID_KEYS, `${basePath}.grid`, errors);
+        validateInteger(grid['x'], `${basePath}.grid.x`, errors, 0, true);
+        validateInteger(grid['y'], `${basePath}.grid.y`, errors, 0, true);
+        validateInteger(grid['w'], `${basePath}.grid.w`, errors, 0, false);
+        validateInteger(grid['h'], `${basePath}.grid.h`, errors, 0, false);
+      }
+    }
+  }
+
+  const elements = input['elements'];
+
+  if (elements !== undefined) {
+    if (!isPlainObject(elements)) {
+      errors.push('theme.elements must be an object.');
+    } else {
+      const allowedElementKeys = THEME_REGISTRY.map((entry) => entry.key);
+
+      validateUnknownKeys(elements, allowedElementKeys, 'theme.elements', errors);
+
+      for (const [key, value] of Object.entries(elements)) {
+        validateElementStyles(value, `theme.elements.${key}`, errors);
+      }
+    }
+  }
+
+  const animations = input['animations'];
+
+  if (animations !== undefined) {
+    if (!isPlainObject(animations)) {
+      errors.push('theme.animations must be an object.');
+    } else {
+      for (const [key, value] of Object.entries(animations)) {
+        if (!SAFE_CLASS_PATTERN.test(key)) {
+          errors.push(`theme.animations.${key} must use a safe CSS class token.`);
+          continue;
+        }
+
+        validateAnimationDefinition(value, `theme.animations.${key}`, errors);
+      }
+    }
+  }
+
+  if (errors.length > 0) {
+    return {
+      valid: false,
+      errors,
+      value: null
+    };
+  }
+
+  return {
+    valid: true,
+    errors: [],
+    value: normaliseThemeDocument(input as Partial<ThemeDocument>)
+  };
+}
\ No newline at end of file
diff --git a/toju-app/src/app/domains/theme/feature/settings/theme-grid-editor.component.html b/toju-app/src/app/domains/theme/feature/settings/theme-grid-editor.component.html
new file mode 100644
index 0000000..6109531
--- /dev/null
+++ b/toju-app/src/app/domains/theme/feature/settings/theme-grid-editor.component.html
@@ -0,0 +1,66 @@
+<div class="theme-grid-editor rounded-2xl border border-border bg-background/50 p-3">
+  <div class="mb-3 flex items-center justify-between gap-3 px-1">
+    <div>
+      <p class="text-sm font-semibold text-foreground">{{ container().label }}</p>
+      <p class="text-xs text-muted-foreground">{{ container().description }}</p>
+    </div>
+
+    <div class="rounded-full bg-secondary px-2.5 py-1 text-[11px] font-medium text-muted-foreground">
+      {{ container().columns }} cols x {{ container().rows }} rows
+    </div>
+  </div>
+
+  <div
+    #canvasRef
+    class="theme-grid-editor__frame relative overflow-hidden rounded-xl border border-border/80"
+    [ngStyle]="frameStyle()"
+  >
+    <div class="theme-grid-editor__grid"></div>
+
+    @for (item of items(); track item.key) {
+      <div
+        class="theme-grid-editor__item absolute"
+        [class.theme-grid-editor__item--selected]="selectedKey() === item.key"
+        [class.theme-grid-editor__item--disabled]="disabled()"
+        [ngStyle]="itemStyle(item)"
+        (click)="selectItem(item.key)"
+        (keydown.enter)="selectItem(item.key)"
+        (keydown.space)="selectItem(item.key)"
+        tabindex="0"
+        role="button"
+        [attr.aria-label]="'Select ' + item.label"
+      >
+        <div
+          class="theme-grid-editor__item-body"
+          (pointerdown)="startMove($event, item)"
+        >
+          <div class="flex items-start justify-between gap-2">
+            <div class="min-w-0">
+              <p class="truncate text-sm font-semibold text-foreground">{{ item.label }}</p>
+              <p class="mt-1 line-clamp-2 text-[11px] leading-4 text-muted-foreground">{{ item.description }}</p>
+            </div>
+
+            <div class="rounded-full bg-background/80 px-2 py-0.5 text-[10px] font-medium text-muted-foreground shadow-sm">
+              {{ item.grid.x }},{{ item.grid.y }} · {{ item.grid.w }}x{{ item.grid.h }}
+            </div>
+          </div>
+        </div>
+
+        <button
+          type="button"
+          class="theme-grid-editor__handle"
+          (pointerdown)="startResize($event, item)"
+          aria-label="Resize {{ item.label }}"
+        ></button>
+      </div>
+    }
+
+    @if (disabled()) {
+      <div
+        class="theme-grid-editor__disabled absolute inset-0 flex items-center justify-center rounded-xl bg-background/75 px-6 text-center text-sm text-muted-foreground backdrop-blur-sm"
+      >
+        Fix JSON validation errors to re-enable the grid editor.
+      </div>
+    }
+  </div>
+</div>
diff --git a/toju-app/src/app/domains/theme/feature/settings/theme-grid-editor.component.scss b/toju-app/src/app/domains/theme/feature/settings/theme-grid-editor.component.scss
new file mode 100644
index 0000000..85dd6f6
--- /dev/null
+++ b/toju-app/src/app/domains/theme/feature/settings/theme-grid-editor.component.scss
@@ -0,0 +1,79 @@
+:host {
+  display: block;
+}
+
+.theme-grid-editor__frame {
+  aspect-ratio: 16 / 9;
+  background:
+    radial-gradient(circle at top, hsl(var(--primary) / 0.08), transparent 45%),
+    linear-gradient(180deg, hsl(var(--background) / 0.96), hsl(var(--card) / 0.98));
+}
+
+.theme-grid-editor__grid {
+  position: absolute;
+  inset: 0;
+  background-image:
+    linear-gradient(to right, hsl(var(--border) / 0.65) 1px, transparent 1px),
+    linear-gradient(to bottom, hsl(var(--border) / 0.65) 1px, transparent 1px);
+  background-size:
+    calc(100% / var(--theme-grid-columns)) calc(100% / var(--theme-grid-rows)),
+    calc(100% / var(--theme-grid-columns)) calc(100% / var(--theme-grid-rows));
+}
+
+.theme-grid-editor__item {
+  padding: 0.35rem;
+}
+
+.theme-grid-editor__item-body {
+  height: 100%;
+  border: 1px solid hsl(var(--border) / 0.8);
+  border-radius: 1rem;
+  background:
+    linear-gradient(180deg, hsl(var(--card) / 0.96), hsl(var(--background) / 0.96)),
+    radial-gradient(circle at top right, hsl(var(--primary) / 0.1), transparent 45%);
+  box-shadow: 0 12px 30px rgb(0 0 0 / 10%);
+  cursor: grab;
+  padding: 0.9rem;
+}
+
+.theme-grid-editor__item:active .theme-grid-editor__item-body {
+  cursor: grabbing;
+}
+
+.theme-grid-editor__item--selected .theme-grid-editor__item-body {
+  border-color: hsl(var(--primary));
+  box-shadow:
+    0 0 0 1px hsl(var(--primary)),
+    0 14px 34px hsl(var(--primary) / 0.18);
+}
+
+.theme-grid-editor__item--disabled .theme-grid-editor__item-body {
+  cursor: not-allowed;
+}
+
+.theme-grid-editor__item:focus-visible {
+  outline: none;
+}
+
+.theme-grid-editor__item:focus-visible .theme-grid-editor__item-body {
+  box-shadow:
+    0 0 0 2px hsl(var(--primary)),
+    0 14px 34px hsl(var(--primary) / 0.18);
+}
+
+.theme-grid-editor__handle {
+  position: absolute;
+  right: 0.75rem;
+  bottom: 0.75rem;
+  height: 0.95rem;
+  width: 0.95rem;
+  border: 0;
+  border-radius: 999px;
+  background: hsl(var(--primary));
+  box-shadow: 0 0 0 3px hsl(var(--background));
+  cursor: nwse-resize;
+}
+
+.theme-grid-editor__disabled {
+  border: 1px dashed hsl(var(--border));
+}
\ No newline at end of file
diff --git a/toju-app/src/app/domains/theme/feature/settings/theme-grid-editor.component.ts b/toju-app/src/app/domains/theme/feature/settings/theme-grid-editor.component.ts
new file mode 100644
index 0000000..8091a4b
--- /dev/null
+++ b/toju-app/src/app/domains/theme/feature/settings/theme-grid-editor.component.ts
@@ -0,0 +1,135 @@
+import {
+  Component,
+  ElementRef,
+  HostListener,
+  computed,
+  inject,
+  input,
+  output,
+  viewChild
+} from '@angular/core';
+import { CommonModule } from '@angular/common';
+
+import {
+  ThemeGridEditorItem,
+  ThemeGridRect,
+  ThemeLayoutContainerDefinition
+} from '../../domain/theme.models';
+
+type DragMode = 'move' | 'resize';
+
+interface DragState {
+  key: string;
+  mode: DragMode;
+  startClientX: number;
+  startClientY: number;
+  startGrid: ThemeGridRect;
+}
+
+@Component({
+  selector: 'app-theme-grid-editor',
+  standalone: true,
+  imports: [CommonModule],
+  templateUrl: './theme-grid-editor.component.html',
+  styleUrl: './theme-grid-editor.component.scss'
+})
+export class ThemeGridEditorComponent {
+  readonly container = input.required<ThemeLayoutContainerDefinition>();
+  readonly items = input.required<ThemeGridEditorItem[]>();
+  readonly selectedKey = input<string | null>(null);
+  readonly disabled = input(false);
+
+  readonly itemChanged = output<{ key: string; grid: ThemeGridRect }>();
+  readonly itemSelected = output<string>();
+
+  private readonly host = inject<ElementRef<HTMLElement>>(ElementRef);
+  private dragState: DragState | null = null;
+
+  readonly canvasRef = viewChild.required<ElementRef<HTMLElement>>('canvasRef');
+  readonly frameStyle = computed(() => ({
+    '--theme-grid-columns': `${this.container().columns}`,
+    '--theme-grid-rows': `${this.container().rows}`
+  }));
+
+  itemStyle(item: ThemeGridEditorItem): Record<string, string> {
+    const { columns, rows } = this.container();
+
+    return {
+      left: `${(item.grid.x / columns) * 100}%`,
+      top: `${(item.grid.y / rows) * 100}%`,
+      width: `${(item.grid.w / columns) * 100}%`,
+      height: `${(item.grid.h / rows) * 100}%`
+    };
+  }
+
+  selectItem(key: string): void {
+    this.itemSelected.emit(key);
+  }
+
+  startMove(event: PointerEvent, item: ThemeGridEditorItem): void {
+    this.startDrag(event, item, 'move');
+  }
+
+  startResize(event: PointerEvent, item: ThemeGridEditorItem): void {
+    this.startDrag(event, item, 'resize');
+  }
+
+  @HostListener('document:pointermove', ['$event'])
+  onPointerMove(event: PointerEvent): void {
+    if (!this.dragState || this.disabled()) {
+      return;
+    }
+
+    const canvasRect = this.canvasRef().nativeElement.getBoundingClientRect();
+    const columnWidth = canvasRect.width / this.container().columns;
+    const rowHeight = canvasRect.height / this.container().rows;
+    const deltaColumns = Math.round((event.clientX - this.dragState.startClientX) / columnWidth);
+    const deltaRows = Math.round((event.clientY - this.dragState.startClientY) / rowHeight);
+    const nextGrid = { ...this.dragState.startGrid };
+
+    if (this.dragState.mode === 'move') {
+      nextGrid.x = this.clamp(deltaColumns + this.dragState.startGrid.x, 0, this.container().columns - nextGrid.w);
+      nextGrid.y = this.clamp(deltaRows + this.dragState.startGrid.y, 0, this.container().rows - nextGrid.h);
+    } else {
+      nextGrid.w = this.clamp(deltaColumns + this.dragState.startGrid.w, 1, this.container().columns - nextGrid.x);
+      nextGrid.h = this.clamp(deltaRows + this.dragState.startGrid.h, 1, this.container().rows - nextGrid.y);
+    }
+
+    this.itemChanged.emit({
+      key: this.dragState.key,
+      grid: nextGrid
+    });
+  }
+
+  @HostListener('document:pointerup')
+  @HostListener('document:pointercancel')
+  onPointerUp(): void {
+    this.dragState = null;
+  }
+
+  @HostListener('document:keydown.escape')
+  onEscape(): void {
+    this.dragState = null;
+  }
+
+  private startDrag(event: PointerEvent, item: ThemeGridEditorItem, mode: DragMode): void {
+    if (this.disabled()) {
+      return;
+    }
+
+    event.preventDefault();
+    event.stopPropagation();
+    this.itemSelected.emit(item.key);
+    this.dragState = {
+      key: item.key,
+      mode,
+      startClientX: event.clientX,
+      startClientY: event.clientY,
+      startGrid: { ...item.grid }
+    };
+  }
+
+  private clamp(value: number, minimum: number, maximum: number): number {
+    return Math.min(Math.max(value, minimum), maximum);
+  }
+}
\ No newline at end of file
diff --git a/toju-app/src/app/domains/theme/feature/settings/theme-json-code-editor.component.ts b/toju-app/src/app/domains/theme/feature/settings/theme-json-code-editor.component.ts
new file mode 100644
index 0000000..370ed48
--- /dev/null
+++ b/toju-app/src/app/domains/theme/feature/settings/theme-json-code-editor.component.ts
@@ -0,0 +1,245 @@
+import {
+  Component,
+  ElementRef,
+  NgZone,
+  OnDestroy,
+  computed,
+  effect,
+  inject,
+  input,
+  output,
+  viewChild
+} from '@angular/core';
+import { indentWithTab } from '@codemirror/commands';
+import { json } from '@codemirror/lang-json';
+import { indentUnit } from '@codemirror/language';
+import { EditorSelection, EditorState } from '@codemirror/state';
+import { oneDark } from '@codemirror/theme-one-dark';
+import { EditorView, keymap } from '@codemirror/view';
+import { basicSetup } from 'codemirror';
+
+const THEME_JSON_EDITOR_THEME = EditorView.theme({
+  '&': {
+    height: '100%',
+    backgroundColor: 'transparent',
+    color: '#e7eef9'
+  },
+  '&.cm-focused': {
+    outline: 'none'
+  },
+  '.cm-scroller': {
+    overflow: 'auto',
+    fontFamily: "'IBM Plex Mono', 'JetBrains Mono', 'Fira Code', monospace",
+    lineHeight: '1.55'
+  },
+  '.cm-content': {
+    minHeight: '100%',
+    padding: '1rem 0',
+    caretColor: '#f8fafc'
+  },
+  '.cm-line': {
+    padding: '0 1rem 0 0.5rem'
+  },
+  '.cm-cursor, .cm-dropCursor': {
+    borderLeftColor: '#f8fafc'
+  },
+  '.cm-gutters': {
+    minHeight: '100%',
+    borderRight: '1px solid #2f405c',
+    backgroundColor: '#172033',
+    color: '#7b8aa5'
+  },
+  '.cm-activeLine': {
+    backgroundColor: 'rgb(148 163 184 / 0.08)'
+  },
+  '.cm-activeLineGutter': {
+    backgroundColor: 'rgb(148 163 184 / 0.12)',
+    color: '#d7e2f2'
+  },
+  '.cm-selectionBackground, &.cm-focused .cm-selectionBackground, ::selection': {
+    backgroundColor: 'rgb(96 165 250 / 0.22)'
+  },
+  '.cm-panels': {
+    backgroundColor: '#111827',
+    color: '#e5eefc',
+    borderBottom: '1px solid #2f405c'
+  },
+  '.cm-searchMatch': {
+    backgroundColor: 'rgb(250 204 21 / 0.18)',
+    outline: '1px solid rgb(250 204 21 / 0.32)'
+  },
+  '.cm-searchMatch.cm-searchMatch-selected': {
+    backgroundColor: 'rgb(250 204 21 / 0.28)'
+  },
+  '.cm-tooltip': {
+    border: '1px solid #314158',
+    backgroundColor: '#111827'
+  },
+  '.cm-tooltip-autocomplete ul li[aria-selected]': {
+    backgroundColor: 'rgb(96 165 250 / 0.18)',
+    color: '#f8fafc'
+  }
+}, { dark: true });
+
+@Component({
+  selector: 'app-theme-json-code-editor',
+  standalone: true,
+  template: `
+    <div
+      class="theme-json-code-editor"
+      [style.minHeight]="editorMinHeight()"
+    >
+      <div
+        #editorHostRef
+        class="theme-json-code-editor__host"
+      ></div>
+    </div>
+  `,
+  styles: `
+    :host {
+      display: block;
+      min-height: 0;
+    }
+
+    .theme-json-code-editor {
+      overflow: hidden;
+      border: 1px solid #2f405c;
+      border-radius: 1rem;
+      background:
+        radial-gradient(circle at top right, rgb(96 165 250 / 0.16), transparent 34%),
+        linear-gradient(180deg, #172033, #0e1625);
+      box-shadow:
+        inset 0 0 0 1px rgb(125 211 252 / 0.08),
+        0 0 0 1px rgb(15 23 42 / 0.16);
+    }
+
+    .theme-json-code-editor:focus-within {
+      box-shadow:
+        inset 0 0 0 1px rgb(125 211 252 / 0.5),
+        0 0 0 3px rgb(14 165 233 / 0.18);
+    }
+
+    .theme-json-code-editor__host {
+      min-height: inherit;
+    }
+  `
+})
+export class ThemeJsonCodeEditorComponent implements OnDestroy {
+  private readonly zone = inject(NgZone);
+
+  readonly editorHostRef = viewChild<ElementRef<HTMLDivElement>>('editorHostRef');
+  readonly value = input.required<string>();
+  readonly fullscreen = input(false);
+  readonly valueChange = output<string>();
+
+  readonly editorMinHeight = computed(() => this.fullscreen() ? 'max(34rem, calc(100vh - 15rem))' : '28rem');
+
+  private editorView: EditorView | null = null;
+  private isApplyingExternalValue = false;
+
+  constructor() {
+    effect(() => {
+      const host = this.editorHostRef();
+
+      if (!host || this.editorView) {
+        return;
+      }
+
+      this.createEditor(host.nativeElement);
+    });
+
+    effect(() => {
+      const nextValue = this.value();
+
+      if (!this.editorView) {
+        return;
+      }
+
+      const currentValue = this.editorView.state.doc.toString();
+
+      if (currentValue === nextValue) {
+        return;
+      }
+
+      this.isApplyingExternalValue = true;
+      this.editorView.dispatch({
+        changes: {
+          from: 0,
+          to: currentValue.length,
+          insert: nextValue
+        }
+      });
+      this.isApplyingExternalValue = false;
+    });
+
+    effect(() => {
+      this.fullscreen();
+
+      queueMicrotask(() => {
+        this.editorView?.requestMeasure();
+      });
+    });
+  }
+
+  ngOnDestroy(): void {
+    this.editorView?.destroy();
+    this.editorView = null;
+  }
+
+  focus(): void {
+    this.editorView?.focus();
+  }
+
+  focusRange(from: number, to = from): void {
+    if (!this.editorView) {
+      return;
+    }
+
+    const documentLength = this.editorView.state.doc.length;
+    const selectionStart = Math.max(0, Math.min(from, documentLength));
+    const selectionEnd = Math.max(selectionStart, Math.min(to, documentLength));
+
+    this.editorView.dispatch({
+      selection: EditorSelection.range(selectionStart, selectionEnd),
+      effects: EditorView.scrollIntoView(selectionStart, { y: 'center' })
+    });
+    this.editorView.focus();
+  }
+
+  private createEditor(host: HTMLDivElement): void {
+    this.zone.runOutsideAngular(() => {
+      this.editorView = new EditorView({
+        state: EditorState.create({
+          doc: this.value(),
+          extensions: [
+            basicSetup,
+            keymap.of([indentWithTab]),
+            indentUnit.of('  '),
+            json(),
+            oneDark,
+            THEME_JSON_EDITOR_THEME,
+            EditorState.tabSize.of(2),
+            EditorView.contentAttributes.of({
+              spellcheck: 'false',
+              autocapitalize: 'off',
+              autocorrect: 'off',
+              'aria-label': 'Theme JSON editor'
+            }),
+            EditorView.updateListener.of((update) => {
+              if (!update.docChanged || this.isApplyingExternalValue) {
+                return;
+              }
+
+              const nextValue = update.state.doc.toString();
+
+              this.zone.run(() => {
+                this.valueChange.emit(nextValue);
+              });
+            })
+          ]
+        }),
+        parent: host
+      });
+    });
+  }
+}
\ No newline at end of file
diff --git a/toju-app/src/app/domains/theme/feature/settings/theme-settings.component.html b/toju-app/src/app/domains/theme/feature/settings/theme-settings.component.html
new file mode 100644
index 0000000..a8fb835
--- /dev/null
+++ b/toju-app/src/app/domains/theme/feature/settings/theme-settings.component.html
@@ -0,0 +1,498 @@
+<div
+  class="theme-settings flex min-h-0 w-full flex-col space-y-4"
+  [class.min-h-full]="isFullscreen()"
+  [class.p-4]="isFullscreen()"
+  [class.theme-settings--fullscreen]="isFullscreen()"
+>
+  <section class="theme-studio-card p-4">
+    <div class="flex flex-wrap items-start justify-between gap-4">
+      <div>
+        <p class="text-xs font-semibold uppercase tracking-[0.18em] text-primary">Theme Studio</p>
+        <h4 class="mt-1 text-xl font-semibold text-foreground">{{ draftTheme().meta.name }}</h4>
+      </div>
+
+      <div class="flex flex-wrap gap-2">
+        <button
+          type="button"
+          (click)="startPicker()"
+          class="inline-flex items-center rounded-full border border-border bg-background px-3 py-1.5 text-sm font-medium text-foreground transition-colors hover:bg-secondary"
+        >
+          Pick UI Element
+        </button>
+        <button
+          type="button"
+          (click)="formatDraft()"
+          class="inline-flex items-center rounded-full border border-border bg-background px-3 py-1.5 text-sm font-medium text-foreground transition-colors hover:bg-secondary"
+        >
+          Format JSON
+        </button>
+        <button
+          type="button"
+          (click)="copyLlmThemeGuide()"
+          class="inline-flex items-center rounded-full border border-border bg-background px-3 py-1.5 text-sm font-medium text-foreground transition-colors hover:bg-secondary"
+        >
+          Copy LLM Guide
+        </button>
+        <button
+          type="button"
+          (click)="applyDraft()"
+          [disabled]="!draftIsValid()"
+          class="inline-flex items-center rounded-full bg-primary px-4 py-1.5 text-sm font-semibold text-primary-foreground transition-colors hover:bg-primary/90 disabled:cursor-not-allowed disabled:opacity-60"
+        >
+          Apply Draft
+        </button>
+        <button
+          type="button"
+          (click)="restoreDefaultTheme()"
+          class="inline-flex items-center rounded-full border border-destructive/25 bg-destructive/10 px-3 py-1.5 text-sm font-medium text-destructive transition-colors hover:bg-destructive/15"
+        >
+          Restore Default
+        </button>
+      </div>
+    </div>
+
+    @if (llmGuideCopyMessage()) {
+      <div class="mt-3 inline-flex rounded-full border border-emerald-500/20 bg-emerald-500/10 px-3 py-1 text-xs font-semibold text-emerald-700">
+        {{ llmGuideCopyMessage() }}
+      </div>
+    }
+
+    <div class="theme-settings__hero-grid mt-4">
+      <div class="theme-settings__hero-stat">
+        <div class="theme-settings__workspace-selector theme-settings__workspace-selector--compact">
+          <label class="theme-settings__workspace-selector-label">Workspace</label>
+          <select
+            class="theme-settings__workspace-select"
+            [value]="activeWorkspace()"
+            (change)="onWorkspaceSelect($event)"
+          >
+            @for (workspace of workspaceTabs; track workspace.key) {
+              <option [value]="workspace.key">{{ workspace.label }}</option>
+            }
+          </select>
+        </div>
+      </div>
+      <div class="theme-settings__hero-stat">
+        <span class="theme-settings__hero-label">Regions</span>
+        <strong class="theme-settings__hero-value">{{ mountedEntryCount() }}</strong>
+      </div>
+      <div class="theme-settings__hero-stat">
+        <span class="theme-settings__hero-label">Draft</span>
+        <strong
+          class="theme-settings__hero-value"
+          [class.text-amber-700]="isDraftDirty()"
+          [class.text-emerald-700]="!isDraftDirty()"
+        >
+          {{ isDraftDirty() ? 'Unsaved changes' : 'In sync' }}
+        </strong>
+      </div>
+    </div>
+
+    @if (statusMessage()) {
+      <div class="mt-3 rounded-2xl border border-primary/20 bg-primary/10 px-4 py-3 text-sm text-primary">
+        {{ statusMessage() }}
+      </div>
+    }
+
+    @if (!draftIsValid()) {
+      <div class="mt-3 rounded-2xl border border-destructive/30 bg-destructive/8 p-4">
+        <p class="text-sm font-semibold text-destructive">The draft is invalid. The last working theme is still active.</p>
+        <ul class="mt-2 space-y-1 text-sm text-destructive/90">
+          @for (error of draftErrors(); track error) {
+            <li>{{ error }}</li>
+          }
+        </ul>
+      </div>
+    }
+  </section>
+
+  <div class="theme-settings__workspace min-h-0 flex-1">
+    <aside class="theme-settings__sidebar">
+      @if (savedThemesAvailable()) {
+        <section class="theme-studio-card p-3.5">
+          <div class="flex items-center justify-between gap-3">
+            <p class="text-sm font-semibold text-foreground">Saved Themes</p>
+            <span class="rounded-full bg-secondary px-2.5 py-1 text-[11px] font-medium text-muted-foreground">
+              {{ savedThemesBusy() ? 'Syncing' : savedThemes().length + ' saved' }}
+            </span>
+          </div>
+
+          <div class="mt-3 flex flex-wrap gap-2">
+            <button
+              type="button"
+              (click)="saveDraftAsNewTheme()"
+              [disabled]="!draftIsValid() || savedThemesBusy()"
+              class="rounded-full border border-border bg-background px-3 py-1.5 text-xs font-medium text-foreground transition-colors hover:bg-secondary disabled:cursor-not-allowed disabled:opacity-60"
+            >
+              Save New
+            </button>
+            <button
+              type="button"
+              (click)="saveDraftToSelectedTheme()"
+              [disabled]="!draftIsValid() || !selectedSavedTheme() || savedThemesBusy()"
+              class="rounded-full border border-border bg-background px-3 py-1.5 text-xs font-medium text-foreground transition-colors hover:bg-secondary disabled:cursor-not-allowed disabled:opacity-60"
+            >
+              Save Selected
+            </button>
+            <button
+              type="button"
+              (click)="useSelectedSavedTheme()"
+              [disabled]="!selectedSavedTheme()?.isValid || (savedThemesBusy() && savedThemes().length === 0)"
+              class="rounded-full border border-border bg-background px-3 py-1.5 text-xs font-medium text-foreground transition-colors hover:bg-secondary disabled:cursor-not-allowed disabled:opacity-60"
+            >
+              Use
+            </button>
+            <button
+              type="button"
+              (click)="editSelectedSavedTheme()"
+              [disabled]="!selectedSavedTheme()?.isValid || (savedThemesBusy() && savedThemes().length === 0)"
+              class="rounded-full border border-border bg-background px-3 py-1.5 text-xs font-medium text-foreground transition-colors hover:bg-secondary disabled:cursor-not-allowed disabled:opacity-60"
+            >
+              Edit
+            </button>
+            <button
+              type="button"
+              (click)="removeSelectedSavedTheme()"
+              [disabled]="!selectedSavedTheme() || (savedThemesBusy() && savedThemes().length === 0)"
+              class="rounded-full border border-destructive/25 bg-destructive/10 px-3 py-1.5 text-xs font-medium text-destructive transition-colors hover:bg-destructive/15 disabled:cursor-not-allowed disabled:opacity-60"
+            >
+              Remove
+            </button>
+            <button
+              type="button"
+              (click)="refreshSavedThemes()"
+              [disabled]="savedThemesBusy() && savedThemes().length === 0"
+              class="rounded-full border border-border bg-background px-3 py-1.5 text-xs font-medium text-foreground transition-colors hover:bg-secondary disabled:cursor-not-allowed disabled:opacity-60"
+            >
+              Refresh
+            </button>
+          </div>
+
+          @if (savedThemes().length > 0) {
+            <div class="theme-settings__saved-theme-list mt-4">
+              @for (savedTheme of savedThemes(); track savedTheme.fileName) {
+                <button
+                  type="button"
+                  (click)="selectSavedTheme(savedTheme.fileName)"
+                  class="theme-settings__saved-theme-button"
+                  [class.theme-settings__saved-theme-button--active]="selectedSavedTheme()?.fileName === savedTheme.fileName"
+                >
+                  <div class="flex items-start justify-between gap-3">
+                    <div>
+                      <p class="text-sm font-semibold text-foreground">{{ savedTheme.themeName }}</p>
+                      <p class="mt-1 font-mono text-[11px] text-muted-foreground">{{ savedTheme.fileName }}</p>
+                    </div>
+
+                    @if (savedTheme.isValid) {
+                      <span class="rounded-full bg-emerald-500/12 px-2 py-0.5 text-[10px] font-medium text-emerald-700">Ready</span>
+                    } @else {
+                      <span class="rounded-full bg-destructive/10 px-2 py-0.5 text-[10px] font-medium text-destructive">Invalid</span>
+                    }
+                  </div>
+
+                  @if (savedTheme.version) {
+                    <p class="mt-2 text-[11px] font-medium text-muted-foreground">v{{ savedTheme.version }}</p>
+                  }
+
+                  @if (savedTheme.description) {
+                    <p class="mt-2 text-xs leading-5 text-muted-foreground">{{ savedTheme.description }}</p>
+                  }
+
+                  @if (savedTheme.error) {
+                    <p class="mt-2 text-xs leading-5 text-destructive">{{ savedTheme.error }}</p>
+                  }
+                </button>
+              }
+            </div>
+          } @else {
+            <div class="mt-4 rounded-2xl border border-dashed border-border bg-background/60 px-4 py-5 text-sm text-muted-foreground">
+              Save the current draft to create your first reusable Electron theme.
+            </div>
+          }
+
+          @if (savedThemesPath()) {
+            <p class="mt-3 font-mono text-[11px] leading-5 text-muted-foreground">{{ savedThemesPath() }}</p>
+          }
+        </section>
+      }
+
+      <section class="theme-studio-card p-3.5">
+        <div class="flex items-center justify-between gap-3">
+          <p class="text-sm font-semibold text-foreground">Explorer</p>
+          <span class="rounded-full bg-secondary px-2.5 py-1 text-[11px] font-medium text-muted-foreground">
+            {{ filteredEntries().length }} shown
+          </span>
+        </div>
+
+        <div class="mt-4">
+          <input
+            type="text"
+            [value]="explorerQuery()"
+            (input)="onExplorerQueryInput($event)"
+            placeholder="Search theme keys"
+            class="theme-settings__search-input mt-2 w-full"
+          />
+        </div>
+
+        <div class="theme-settings__entry-list mt-4">
+          @for (entry of filteredEntries(); track entry.key) {
+            <button
+              type="button"
+              (click)="selectThemeEntry(entry.key)"
+              class="theme-settings__entry-button"
+              [class.theme-settings__entry-button--active]="selectedElementKey() === entry.key"
+            >
+              <div class="flex items-center justify-between gap-2">
+                <span class="text-sm font-semibold text-foreground">{{ entry.label }}</span>
+                @if (isMounted(entry)) {
+                  <span class="rounded-full bg-emerald-500/12 px-2 py-0.5 text-[10px] font-medium text-emerald-700">Mounted</span>
+                }
+              </div>
+              <span class="mt-1 block font-mono text-[11px] text-muted-foreground">{{ entry.key }}</span>
+              <span class="mt-2 block text-xs leading-5 text-muted-foreground">{{ entry.description }}</span>
+            </button>
+          } @empty {
+            <div class="rounded-2xl border border-dashed border-border bg-background/60 px-4 py-5 text-sm text-muted-foreground">
+              No registered theme keys match this filter.
+            </div>
+          }
+        </div>
+      </section>
+    </aside>
+
+    <main class="theme-settings__main">
+      <section class="theme-studio-card p-3.5">
+        <div class="flex flex-wrap items-start justify-between gap-4">
+          <div>
+            @if (selectedElement()) {
+              <div class="flex flex-wrap items-center gap-2">
+                <span class="text-base font-semibold text-foreground">{{ selectedElement()!.label }}</span>
+                <span class="rounded-full bg-secondary px-2 py-0.5 font-mono text-[11px] text-muted-foreground">{{ selectedElement()!.key }}</span>
+                @if (selectedElement()!.container) {
+                  <span class="rounded-full bg-secondary px-2 py-0.5 text-[11px] font-medium text-muted-foreground">{{
+                    selectedElement()!.container
+                  }}</span>
+                }
+              </div>
+              <p class="mt-2 text-sm leading-6 text-muted-foreground">{{ selectedElement()!.description }}</p>
+            }
+          </div>
+
+          @if (selectedElement()) {
+            <div class="flex flex-wrap gap-2">
+              <button
+                type="button"
+                (click)="jumpToStyles()"
+                class="rounded-full border border-border bg-background px-3 py-1.5 text-xs font-medium text-foreground transition-colors hover:bg-secondary"
+              >
+                Open styles in JSON
+              </button>
+              @if (selectedElement()!.layoutEditable) {
+                <button
+                  type="button"
+                  (click)="jumpToLayout()"
+                  class="rounded-full border border-border bg-background px-3 py-1.5 text-xs font-medium text-foreground transition-colors hover:bg-secondary"
+                >
+                  Open layout in JSON
+                </button>
+              }
+            </div>
+          }
+        </div>
+
+        @if (selectedElementCapabilities().length > 0) {
+          <div class="mt-4 flex flex-wrap gap-2">
+            @for (capability of selectedElementCapabilities(); track capability) {
+              <span class="rounded-full bg-secondary px-2.5 py-1 text-[11px] font-medium text-muted-foreground">{{ capability }}</span>
+            }
+          </div>
+        }
+      </section>
+
+      @if (activeWorkspace() === 'editor') {
+        <section class="theme-studio-card theme-settings__editor-card p-4">
+          <div class="flex flex-wrap items-start justify-between gap-4 border-b border-border pb-3">
+            <p class="text-sm font-semibold text-foreground">Theme JSON</p>
+
+            <div class="flex flex-wrap gap-2 text-[11px] font-medium text-muted-foreground">
+              <span class="rounded-full bg-secondary px-2.5 py-1">{{ draftLineCount() }} lines</span>
+              <span class="rounded-full bg-secondary px-2.5 py-1">{{ draftCharacterCount() }} chars</span>
+              <span class="rounded-full bg-secondary px-2.5 py-1">{{ draftErrorCount() }} errors</span>
+              <span class="rounded-full bg-slate-900 px-2.5 py-1 text-slate-200">IDE editor</span>
+            </div>
+          </div>
+
+          <div class="theme-settings__editor-panel pt-3">
+            <app-theme-json-code-editor
+              #jsonEditorRef
+              [value]="draftText()"
+              [fullscreen]="isFullscreen()"
+              (valueChange)="onDraftEditorValueChange($event)"
+            />
+          </div>
+        </section>
+      }
+
+      @if (activeWorkspace() === 'inspector') {
+        <div class="space-y-6">
+          <section class="theme-studio-card p-4">
+            <div class="flex items-center justify-between gap-3">
+              <p class="text-sm font-semibold text-foreground">Selection</p>
+
+              <button
+                type="button"
+                (click)="startPicker()"
+                class="rounded-full border border-border bg-background px-3 py-1.5 text-xs font-medium text-foreground transition-colors hover:bg-secondary"
+              >
+                Pick live element
+              </button>
+            </div>
+
+            @if (selectedElement()) {
+              <div class="mt-4 rounded-2xl border border-border/80 bg-background/65 p-4">
+                <div class="flex items-center gap-2">
+                  <p class="text-base font-semibold text-foreground">{{ selectedElement()!.label }}</p>
+                  <span class="rounded-full bg-secondary px-2 py-0.5 font-mono text-[11px] text-muted-foreground">{{ selectedElement()!.key }}</span>
+                  @if (isMounted(selectedElement()!)) {
+                    <span class="rounded-full bg-emerald-500/12 px-2 py-0.5 text-[11px] font-medium text-emerald-700">Mounted now</span>
+                  }
+                </div>
+                <p class="mt-2 text-sm leading-6 text-muted-foreground">{{ selectedElement()!.description }}</p>
+              </div>
+            }
+          </section>
+
+          <section class="theme-studio-card p-4">
+            <div class="flex items-center justify-between gap-3">
+              <p class="text-sm font-semibold text-foreground">Schema Hints</p>
+
+              <button
+                type="button"
+                (click)="addStarterAnimation()"
+                [disabled]="!draftIsValid()"
+                class="rounded-full border border-border bg-background px-3 py-1.5 text-xs font-medium text-foreground transition-colors hover:bg-secondary disabled:cursor-not-allowed disabled:opacity-60"
+              >
+                Add fade animation
+              </button>
+            </div>
+
+            <div class="mt-4 grid gap-3 xl:grid-cols-2">
+              @for (field of visiblePropertyHints(); track field.key) {
+                <button
+                  type="button"
+                  (click)="applySuggestedProperty(field.key)"
+                  [disabled]="!draftIsValid()"
+                  class="rounded-2xl border border-border/80 bg-background/65 p-3 text-left transition-colors hover:bg-secondary/45 disabled:cursor-not-allowed disabled:opacity-60"
+                >
+                  <div class="flex items-start justify-between gap-3">
+                    <div>
+                      <p class="font-mono text-sm font-semibold text-foreground">{{ field.key }}</p>
+                      <p class="mt-1 text-xs leading-5 text-muted-foreground">{{ field.description }}</p>
+                    </div>
+                    <span class="rounded-full bg-secondary px-2 py-0.5 text-[10px] font-medium text-muted-foreground">{{ field.type }}</span>
+                  </div>
+                  <div class="mt-3 inline-flex rounded-full bg-primary/10 px-2.5 py-1 font-mono text-[11px] text-primary">
+                    {{ field.example }}
+                  </div>
+                </button>
+              }
+            </div>
+          </section>
+
+          <section class="theme-studio-card p-5">
+            <p class="text-sm font-semibold text-foreground">Animation Keys</p>
+
+            @if (animationKeys().length > 0) {
+              <div class="mt-4 flex flex-wrap gap-2">
+                @for (animationKey of animationKeys(); track animationKey) {
+                  <button
+                    type="button"
+                    (click)="jumpToAnimation(animationKey)"
+                    class="rounded-full border border-border bg-background px-3 py-1.5 font-mono text-[11px] text-foreground transition-colors hover:bg-secondary"
+                  >
+                    {{ animationKey }}
+                  </button>
+                }
+              </div>
+            } @else {
+              <div class="mt-4 rounded-2xl border border-dashed border-border bg-background/60 px-4 py-5 text-sm text-muted-foreground">
+                No custom animation keys yet.
+              </div>
+            }
+
+            <div class="mt-4 rounded-2xl border border-border/80 bg-background/65 p-4">
+              <div class="flex flex-wrap gap-2">
+                @for (field of THEME_ANIMATION_FIELDS; track field.key) {
+                  <span class="rounded-full bg-secondary px-2.5 py-1 font-mono text-[11px] text-foreground/80">{{ field.key }}</span>
+                }
+              </div>
+            </div>
+          </section>
+        </div>
+      }
+
+      @if (activeWorkspace() === 'layout') {
+        <section class="theme-studio-card p-4">
+          <div class="flex flex-wrap items-start justify-between gap-4">
+            <p class="text-sm font-semibold text-foreground">Layout Grid</p>
+
+            <div class="flex flex-wrap gap-2">
+              @for (container of layoutContainers; track container.key) {
+                <button
+                  type="button"
+                  (click)="selectContainer(container.key)"
+                  class="rounded-full border border-border bg-background px-3 py-1.5 text-xs font-medium text-foreground transition-colors hover:bg-secondary"
+                  [class.bg-primary/10]="selectedContainer() === container.key"
+                  [class.border-primary/40]="selectedContainer() === container.key"
+                >
+                  {{ container.label }}
+                </button>
+              }
+
+              <button
+                type="button"
+                (click)="resetSelectedContainer()"
+                [disabled]="!draftIsValid()"
+                class="rounded-full border border-border bg-background px-3 py-1.5 text-xs font-medium text-foreground transition-colors hover:bg-secondary disabled:cursor-not-allowed disabled:opacity-60"
+              >
+                Reset Container
+              </button>
+            </div>
+          </div>
+
+          <div class="mt-5">
+            <app-theme-grid-editor
+              [container]="selectedContainer() === 'appShell' ? layoutContainers[0] : layoutContainers[1]"
+              [items]="selectedContainerItems()"
+              [selectedKey]="selectedElementKey()"
+              [disabled]="!draftIsValid()"
+              (itemChanged)="handleGridChange($event)"
+              (itemSelected)="handleGridSelection($event)"
+            />
+          </div>
+
+          @if (selectedElementGrid()) {
+            <div class="mt-4 grid gap-3 sm:grid-cols-4">
+              <div class="rounded-2xl border border-border/80 bg-background/65 p-3">
+                <p class="text-[11px] font-semibold uppercase tracking-[0.18em] text-muted-foreground">x</p>
+                <p class="mt-2 font-mono text-lg font-semibold text-foreground">{{ selectedElementGrid()!.grid.x }}</p>
+              </div>
+              <div class="rounded-2xl border border-border/80 bg-background/65 p-3">
+                <p class="text-[11px] font-semibold uppercase tracking-[0.18em] text-muted-foreground">y</p>
+                <p class="mt-2 font-mono text-lg font-semibold text-foreground">{{ selectedElementGrid()!.grid.y }}</p>
+              </div>
+              <div class="rounded-2xl border border-border/80 bg-background/65 p-3">
+                <p class="text-[11px] font-semibold uppercase tracking-[0.18em] text-muted-foreground">w</p>
+                <p class="mt-2 font-mono text-lg font-semibold text-foreground">{{ selectedElementGrid()!.grid.w }}</p>
+              </div>
+              <div class="rounded-2xl border border-border/80 bg-background/65 p-3">
+                <p class="text-[11px] font-semibold uppercase tracking-[0.18em] text-muted-foreground">h</p>
+                <p class="mt-2 font-mono text-lg font-semibold text-foreground">{{ selectedElementGrid()!.grid.h }}</p>
+              </div>
+            </div>
+          }
+        </section>
+      }
+    </main>
+  </div>
+</div>
diff --git a/toju-app/src/app/domains/theme/feature/settings/theme-settings.component.scss b/toju-app/src/app/domains/theme/feature/settings/theme-settings.component.scss
new file mode 100644
index 0000000..083eaaf
--- /dev/null
+++ b/toju-app/src/app/domains/theme/feature/settings/theme-settings.component.scss
@@ -0,0 +1,117 @@
+:host {
+  display: block;
+  width: 100%;
+  min-height: 100%;
+}
+
+.theme-settings {
+  min-width: 0;
+}
+
+.theme-settings__workspace-selector {
+  display: flex;
+  flex-direction: column;
+  gap: 0.45rem;
+}
+
+.theme-settings__workspace-selector--compact {
+  gap: 0.35rem;
+}
+
+.theme-settings__workspace-selector-label {
+  font-size: 0.69rem;
+  font-weight: 700;
+  letter-spacing: 0.16em;
+  text-transform: uppercase;
+  color: hsl(var(--muted-foreground));
+}
+
+.theme-settings__workspace-select {
+  width: 100%;
+  border: 1px solid hsl(var(--border));
+  border-radius: 0.85rem;
+  background: hsl(var(--background) / 0.82);
+  padding: 0.65rem 0.8rem;
+  font-size: 0.88rem;
+  font-weight: 600;
+  color: hsl(var(--foreground));
+  outline: none;
+  transition:
+    border-color 160ms ease,
+    box-shadow 160ms ease,
+    background-color 160ms ease;
+}
+
+.theme-settings__workspace-select:focus {
+  border-color: hsl(var(--primary) / 0.4);
+  box-shadow: 0 0 0 3px hsl(var(--primary) / 0.12);
+}
+
+.theme-settings__workspace-selector--compact .theme-settings__workspace-select {
+  padding: 0.55rem 0.7rem;
+  font-size: 0.84rem;
+}
+
+.theme-settings__editor-card {
+  display: flex;
+  min-height: 0;
+  flex-direction: column;
+}
+
+.theme-settings__editor-panel {
+  display: flex;
+  min-height: 0;
+  flex: 1 1 auto;
+  flex-direction: column;
+}
+
+.theme-settings__saved-theme-list {
+  display: flex;
+  flex-direction: column;
+  gap: 0.7rem;
+}
+
+.theme-settings__saved-theme-button {
+  width: 100%;
+  border: 1px solid hsl(var(--border) / 0.8);
+  border-radius: 1rem;
+  background: hsl(var(--background) / 0.65);
+  padding: 0.85rem;
+  text-align: left;
+  transition:
+    border-color 160ms ease,
+    background-color 160ms ease,
+    transform 160ms ease;
+}
+
+.theme-settings__saved-theme-button:hover {
+  background: hsl(var(--secondary) / 0.45);
+}
+
+.theme-settings__saved-theme-button--active {
+  border-color: hsl(var(--primary) / 0.38);
+  background: hsl(var(--primary) / 0.08);
+}
+
+.theme-json-editor-panel__header {
+  min-width: 0;
+}
+
+.theme-json-editor-panel__title {
+  font-size: 0.85rem;
+  font-weight: 700;
+  color: hsl(var(--foreground));
+}
+
+.theme-json-editor-panel__caption {
+  margin-top: 0.2rem;
+  font-size: 0.74rem;
+  line-height: 1.45;
+  color: hsl(var(--muted-foreground));
+}
+
+.theme-settings--fullscreen .theme-settings__editor-panel app-theme-json-code-editor {
+  display: block;
+  min-height: 0;
+  flex: 1 1 auto;
+}
\ No newline at end of file
diff --git a/toju-app/src/app/domains/theme/feature/settings/theme-settings.component.ts b/toju-app/src/app/domains/theme/feature/settings/theme-settings.component.ts
new file mode 100644
index 0000000..e74b6dc
--- /dev/null
+++ b/toju-app/src/app/domains/theme/feature/settings/theme-settings.component.ts
@@ -0,0 +1,473 @@
+import {
+  Component,
+  computed,
+  effect,
+  inject,
+  signal,
+  viewChild
+} from '@angular/core';
+import { CommonModule } from '@angular/common';
+
+import { SettingsModalService } from '../../../../core/services/settings-modal.service';
+import {
+  ThemeContainerKey,
+  ThemeElementStyleProperty,
+  ThemeRegistryEntry
+} from '../../domain/theme.models';
+import {
+  THEME_ANIMATION_FIELDS as THEME_ANIMATION_FIELD_HINTS,
+  THEME_ELEMENT_STYLE_FIELDS,
+  createAnimationStarterDefinition,
+  getSuggestedFieldDefault
+} from '../../domain/theme.schema';
+import { ElementPickerService } from '../../application/element-picker.service';
+import { LayoutSyncService } from '../../application/layout-sync.service';
+import { ThemeLibraryService } from '../../application/theme-library.service';
+import { ThemeRegistryService } from '../../application/theme-registry.service';
+import { ThemeService } from '../../application/theme.service';
+import { THEME_LLM_GUIDE } from '../../domain/theme-llm-guide';
+import { ThemeGridEditorComponent } from './theme-grid-editor.component';
+import { ThemeJsonCodeEditorComponent } from './theme-json-code-editor.component';
+
+type JumpSection = 'elements' | 'layout' | 'animations';
+type ThemeStudioWorkspace = 'editor' | 'inspector' | 'layout';
+
+@Component({
+  selector: 'app-theme-settings',
+  standalone: true,
+  imports: [
+    CommonModule,
+    ThemeGridEditorComponent,
+    ThemeJsonCodeEditorComponent
+  ],
+  templateUrl: './theme-settings.component.html',
+  styleUrl: './theme-settings.component.scss'
+})
+export class ThemeSettingsComponent {
+  private readonly modal = inject(SettingsModalService);
+  private readonly theme = inject(ThemeService);
+  private readonly themeLibrary = inject(ThemeLibraryService);
+  private readonly registry = inject(ThemeRegistryService);
+  private readonly picker = inject(ElementPickerService);
+  private readonly layoutSync = inject(LayoutSyncService);
+
+  readonly editorRef = viewChild<ThemeJsonCodeEditorComponent>('jsonEditorRef');
+
+  readonly draftText = this.theme.draftText;
+  readonly draftErrors = this.theme.draftErrors;
+  readonly draftIsValid = this.theme.draftIsValid;
+  readonly statusMessage = this.theme.statusMessage;
+  readonly isDraftDirty = this.theme.isDraftDirty;
+  readonly isFullscreen = this.modal.themeStudioFullscreen;
+  readonly draftTheme = this.theme.draftTheme;
+  readonly THEME_ANIMATION_FIELDS = THEME_ANIMATION_FIELD_HINTS;
+  readonly animationKeys = this.theme.knownAnimationClasses;
+  readonly layoutContainers = this.layoutSync.containers();
+  readonly themeEntries = this.registry.entries();
+  readonly workspaceTabs: ReadonlyArray<{ key: ThemeStudioWorkspace; label: string; description: string }> = [
+    {
+      key: 'editor',
+      label: 'JSON Editor',
+      description: 'Edit the raw theme document in a fixed-contrast code view.'
+    },
+    {
+      key: 'inspector',
+      label: 'Element Inspector',
+      description: 'Browse themeable regions, supported overrides, and starter values.'
+    },
+    {
+      key: 'layout',
+      label: 'Layout Studio',
+      description: 'Move shells around the grid without hunting through JSON.'
+    }
+  ];
+  readonly mountedKeyCounts = computed(() => this.registry.mountedKeyCounts());
+  readonly activeWorkspace = signal<ThemeStudioWorkspace>('editor');
+  readonly explorerQuery = signal('');
+
+  readonly selectedContainer = signal<ThemeContainerKey>('roomLayout');
+  readonly selectedElementKey = signal<string>('chatRoomMainPanel');
+  readonly selectedElement = computed(() => this.registry.getDefinition(this.selectedElementKey()));
+  readonly selectedElementCapabilities = computed(() => {
+    const selected = this.selectedElement();
+
+    if (!selected) {
+      return [] as string[];
+    }
+
+    return [
+      selected.layoutEditable ? 'Layout editable' : null,
+      selected.supportsTextOverride ? 'Text override' : null,
+      selected.supportsLink ? 'Safe external link' : null,
+      selected.supportsIcon ? 'Icon slot' : null
+    ].filter((value): value is string => value !== null);
+  });
+  readonly selectedContainerItems = computed(() => this.layoutSync.itemsForContainer(this.selectedContainer()));
+  readonly selectedElementGrid = computed(() => {
+    return this.selectedContainerItems().find((item) => item.key === this.selectedElementKey()) ?? null;
+  });
+  readonly visiblePropertyHints = computed(() => {
+    const selected = this.selectedElement();
+
+    return THEME_ELEMENT_STYLE_FIELDS.filter((field) => {
+      if (field.key === 'textOverride' && !selected?.supportsTextOverride) {
+        return false;
+      }
+
+      if (field.key === 'link' && !selected?.supportsLink) {
+        return false;
+      }
+
+      if (field.key === 'icon' && !selected?.supportsIcon) {
+        return false;
+      }
+
+      return true;
+    });
+  });
+  readonly mountedEntries = computed(() => {
+    return this.themeEntries.filter((entry) => entry.pickerVisible || entry.layoutEditable);
+  });
+  readonly filteredEntries = computed(() => {
+    const query = this.explorerQuery().trim().toLowerCase();
+
+    if (!query) {
+      return this.mountedEntries();
+    }
+
+    return this.mountedEntries().filter((entry) => {
+      const haystack = `${entry.label} ${entry.key} ${entry.description} ${entry.category}`.toLowerCase();
+
+      return haystack.includes(query);
+    });
+  });
+  readonly draftLineCount = computed(() => this.draftText().split('\n').length);
+  readonly draftCharacterCount = computed(() => this.draftText().length);
+  readonly draftErrorCount = computed(() => this.draftErrors().length);
+  readonly mountedEntryCount = computed(() => this.mountedEntries().length);
+  readonly llmGuideCopyMessage = signal<string | null>(null);
+  readonly savedThemesAvailable = this.themeLibrary.isAvailable;
+  readonly savedThemes = this.themeLibrary.entries;
+  readonly savedThemesBusy = this.themeLibrary.isBusy;
+  readonly savedThemesPath = this.themeLibrary.savedThemesPath;
+  readonly selectedSavedTheme = this.themeLibrary.selectedEntry;
+
+  private llmGuideCopyTimeoutId: ReturnType<typeof setTimeout> | null = null;
+
+  constructor() {
+    if (this.savedThemesAvailable()) {
+      void this.themeLibrary.refresh();
+    }
+
+    effect(() => {
+      const pickedKey = this.picker.selectedKey();
+
+      if (!pickedKey) {
+        return;
+      }
+
+      this.activeWorkspace.set('inspector');
+      this.selectThemeEntry(pickedKey, 'elements');
+    });
+
+    effect(() => {
+      if (!this.isFullscreen()) {
+        return;
+      }
+
+      queueMicrotask(() => {
+        this.focusEditor();
+      });
+    });
+  }
+
+  onDraftEditorValueChange(value: string): void {
+    this.theme.updateDraftText(value);
+  }
+
+  applyDraft(): void {
+    this.theme.applyDraft();
+  }
+
+  setWorkspace(workspace: ThemeStudioWorkspace): void {
+    this.activeWorkspace.set(workspace);
+
+    if (workspace === 'layout') {
+      const selected = this.selectedElement();
+
+      if (selected?.container) {
+        this.selectedContainer.set(selected.container);
+      }
+    }
+
+    if (workspace === 'editor') {
+      this.focusEditor();
+    }
+  }
+
+  onWorkspaceSelect(event: Event): void {
+    const select = event.target as HTMLSelectElement;
+
+    this.setWorkspace(select.value as ThemeStudioWorkspace);
+  }
+
+  onExplorerQueryInput(event: Event): void {
+    const input = event.target as HTMLInputElement;
+
+    this.explorerQuery.set(input.value);
+  }
+
+  formatDraft(): void {
+    this.theme.formatDraft();
+    this.focusEditor();
+  }
+
+  async copyLlmThemeGuide(): Promise<void> {
+    const copied = await this.copyTextToClipboard(THEME_LLM_GUIDE);
+
+    this.setLlmGuideCopyMessage(copied
+      ? 'LLM guide copied.'
+      : 'Manual copy opened.');
+  }
+
+  startPicker(): void {
+    this.picker.start('theme');
+  }
+
+  selectSavedTheme(fileName: string): void {
+    this.themeLibrary.select(fileName);
+  }
+
+  async refreshSavedThemes(): Promise<void> {
+    await this.themeLibrary.refresh();
+  }
+
+  async saveDraftAsNewTheme(): Promise<void> {
+    await this.themeLibrary.saveDraftAsNewTheme();
+  }
+
+  async saveDraftToSelectedTheme(): Promise<void> {
+    await this.themeLibrary.saveDraftToSelectedTheme();
+  }
+
+  async useSelectedSavedTheme(): Promise<void> {
+    await this.themeLibrary.useSelectedTheme();
+  }
+
+  async editSelectedSavedTheme(): Promise<void> {
+    const opened = await this.themeLibrary.openSelectedThemeInDraft();
+
+    if (!opened) {
+      return;
+    }
+
+    this.setWorkspace('editor');
+    this.focusEditor();
+  }
+
+  async removeSelectedSavedTheme(): Promise<void> {
+    const selectedSavedTheme = this.selectedSavedTheme();
+
+    if (!selectedSavedTheme) {
+      return;
+    }
+
+    const confirmed = window.confirm(`Delete saved theme "${selectedSavedTheme.themeName}"?`);
+
+    if (!confirmed) {
+      return;
+    }
+
+    await this.themeLibrary.removeSelectedTheme();
+  }
+
+  restoreDefaultTheme(): void {
+    this.theme.resetToDefault('button');
+    this.activeWorkspace.set('editor');
+    this.selectedContainer.set('roomLayout');
+    this.selectedElementKey.set('chatRoomMainPanel');
+    this.focusJsonAnchor('elements', 'chatRoomMainPanel');
+  }
+
+  selectThemeEntry(key: string, section: JumpSection = 'elements'): void {
+    const definition = this.registry.getDefinition(key);
+
+    if (!definition) {
+      return;
+    }
+
+    if (section === 'layout') {
+      this.activeWorkspace.set('layout');
+    } else if (section === 'animations') {
+      this.activeWorkspace.set('editor');
+    } else {
+      this.activeWorkspace.set('inspector');
+    }
+
+    this.selectedElementKey.set(key);
+
+    if (definition.container) {
+      this.selectedContainer.set(definition.container);
+    }
+  }
+
+  selectContainer(containerKey: ThemeContainerKey): void {
+    this.activeWorkspace.set('layout');
+    this.selectedContainer.set(containerKey);
+
+    const matchingItem = this.layoutSync.itemsForContainer(containerKey)[0];
+
+    if (matchingItem) {
+      this.selectedElementKey.set(matchingItem.key);
+    }
+  }
+
+  applySuggestedProperty(property: ThemeElementStyleProperty): void {
+    if (!this.draftIsValid()) {
+      return;
+    }
+
+    const value = getSuggestedFieldDefault(property, this.animationKeys());
+
+    this.theme.setElementStyle(this.selectedElementKey(), property, value);
+  }
+
+  addStarterAnimation(): void {
+    if (!this.draftIsValid()) {
+      return;
+    }
+
+    this.theme.setAnimation('theme-fade-in', createAnimationStarterDefinition());
+  }
+
+  handleGridChange(event: { key: string; grid: { x: number; y: number; w: number; h: number } }): void {
+    this.layoutSync.updateGrid(event.key, event.grid);
+  }
+
+  handleGridSelection(key: string): void {
+    this.selectThemeEntry(key, 'layout');
+  }
+
+  resetSelectedContainer(): void {
+    this.layoutSync.resetContainer(this.selectedContainer());
+  }
+
+  jumpToLayout(): void {
+    this.activeWorkspace.set('editor');
+    this.focusJsonAnchor('layout', this.selectedElementKey());
+  }
+
+  jumpToStyles(): void {
+    this.activeWorkspace.set('editor');
+    this.focusJsonAnchor('elements', this.selectedElementKey());
+  }
+
+  jumpToAnimation(animationKey: string): void {
+    this.activeWorkspace.set('editor');
+    this.focusJsonAnchor('animations', animationKey);
+  }
+
+  isMounted(entry: ThemeRegistryEntry): boolean {
+    return (this.mountedKeyCounts()[entry.key] ?? 0) > 0;
+  }
+
+  private focusEditor(): void {
+    queueMicrotask(() => {
+      this.editorRef()?.focus();
+    });
+  }
+
+  private focusJsonAnchor(section: JumpSection, key: string): void {
+    queueMicrotask(() => {
+      const editor = this.editorRef();
+
+      if (!editor) {
+        return;
+      }
+
+      let text = this.draftText();
+      let anchorIndex = this.findAnchorIndex(text, section, key);
+
+      if (anchorIndex === -1 && this.draftIsValid()) {
+        if (section === 'elements') {
+          this.theme.ensureElementEntry(key);
+        } else if (section === 'layout') {
+          this.theme.ensureLayoutEntry(key);
+        } else if (section === 'animations') {
+          this.theme.setAnimation(key, createAnimationStarterDefinition(), false);
+        }
+
+        text = this.draftText();
+        anchorIndex = this.findAnchorIndex(text, section, key);
+      }
+
+      if (anchorIndex === -1) {
+        editor.focus();
+        return;
+      }
+
+      const selectionEnd = Math.min(anchorIndex + key.length + 2, text.length);
+
+      editor.focusRange(anchorIndex, selectionEnd);
+    });
+  }
+
+  private async copyTextToClipboard(value: string): Promise<boolean> {
+    if (navigator.clipboard?.writeText) {
+      try {
+        await navigator.clipboard.writeText(value);
+        return true;
+      } catch {}
+    }
+
+    const textarea = document.createElement('textarea');
+
+    textarea.value = value;
+    textarea.setAttribute('readonly', 'true');
+    textarea.style.position = 'fixed';
+    textarea.style.opacity = '0';
+    textarea.style.pointerEvents = 'none';
+    document.body.appendChild(textarea);
+    textarea.select();
+
+    try {
+      const copied = document.execCommand('copy');
+
+      if (copied) {
+        return true;
+      }
+    } catch {
+      window.prompt('Copy this LLM theme guide', value);
+      return false;
+    } finally {
+      document.body.removeChild(textarea);
+    }
+
+    window.prompt('Copy this LLM theme guide', value);
+    return false;
+  }
+
+  private setLlmGuideCopyMessage(message: string): void {
+    this.llmGuideCopyMessage.set(message);
+
+    if (this.llmGuideCopyTimeoutId) {
+      clearTimeout(this.llmGuideCopyTimeoutId);
+    }
+
+    this.llmGuideCopyTimeoutId = setTimeout(() => {
+      this.llmGuideCopyMessage.set(null);
+      this.llmGuideCopyTimeoutId = null;
+    }, 4000);
+  }
+
+  private findAnchorIndex(text: string, section: JumpSection, key: string): number {
+    const sectionAnchor = `"${section}": {`;
+    const sectionIndex = text.indexOf(sectionAnchor);
+
+    if (sectionIndex === -1) {
+      return -1;
+    }
+
+    return text.indexOf(`"${key}"`, sectionIndex);
+  }
+}
\ No newline at end of file
diff --git a/toju-app/src/app/domains/theme/feature/theme-node.directive.ts b/toju-app/src/app/domains/theme/feature/theme-node.directive.ts
new file mode 100644
index 0000000..b649de5
--- /dev/null
+++ b/toju-app/src/app/domains/theme/feature/theme-node.directive.ts
@@ -0,0 +1,248 @@
+import {
+  Directive,
+  ElementRef,
+  HostListener,
+  effect,
+  inject,
+  input
+} from '@angular/core';
+
+import { ExternalLinkService } from '../../../core/platform';
+import { ElementPickerService } from '../application/element-picker.service';
+import { ThemeRegistryService } from '../application/theme-registry.service';
+import { ThemeService } from '../application/theme.service';
+
+function looksLikeImageReference(value: string): boolean {
+  return value.startsWith('url(')
+    || value.startsWith('http://')
+    || value.startsWith('https://')
+    || value.startsWith('/')
+    || value.startsWith('./');
+}
+
+@Directive({
+  selector: '[appThemeNode]',
+  standalone: true
+})
+export class ThemeNodeDirective {
+  readonly themeKey = input.required<string>({ alias: 'appThemeNode' });
+
+  private readonly host = inject<ElementRef<HTMLElement>>(ElementRef);
+  private readonly theme = inject(ThemeService);
+  private readonly registry = inject(ThemeRegistryService);
+  private readonly picker = inject(ElementPickerService);
+  private readonly externalLinks = inject(ExternalLinkService);
+
+  private appliedStyleKeys = new Set<string>();
+  private appliedClasses = new Set<string>();
+  private originalTextContent = new WeakMap<HTMLElement, string>();
+  private registeredKey: string | null = null;
+
+  constructor() {
+    effect(() => {
+      const key = this.themeKey();
+      const definition = this.registry.getDefinition(key);
+      const host = this.host.nativeElement;
+
+      host.dataset['themeKey'] = key;
+      host.dataset['themeLabel'] = definition?.label ?? key;
+
+      if (this.registeredKey && this.registeredKey !== key) {
+        this.registry.unregisterHost(this.registeredKey, host);
+      }
+
+      if (this.registeredKey !== key) {
+        this.registry.registerHost(key, host);
+        this.registeredKey = key;
+      }
+    });
+
+    effect(() => {
+      this.applyThemeStyles();
+      this.applyAnimationClasses();
+      this.applyTextOverride();
+      this.applyIconOverride();
+      this.applyLinkState();
+      this.applyPickerState();
+    });
+  }
+
+  @HostListener('keydown.enter', ['$event'])
+  onEnterKey(event: Event): void {
+    this.openConfiguredLink(event);
+  }
+
+  @HostListener('click', ['$event'])
+  onClick(event: MouseEvent): void {
+    this.openConfiguredLink(event);
+  }
+
+  ngOnDestroy(): void {
+    if (this.registeredKey) {
+      this.registry.unregisterHost(this.registeredKey, this.host.nativeElement);
+      this.registeredKey = null;
+    }
+
+    this.clearAppliedStyles();
+    this.clearAppliedClasses();
+    this.restoreTextTarget();
+    this.resetIconTarget();
+  }
+
+  private applyThemeStyles(): void {
+    const styles = this.theme.getHostStyles(this.themeKey());
+
+    this.clearAppliedStyles();
+
+    for (const [styleKey, styleValue] of Object.entries(styles)) {
+      this.host.nativeElement.style.setProperty(styleKey, styleValue);
+      this.appliedStyleKeys.add(styleKey);
+    }
+  }
+
+  private applyAnimationClasses(): void {
+    this.clearAppliedClasses();
+
+    const animationClass = this.theme.getAnimationClass(this.themeKey());
+
+    if (!animationClass) {
+      return;
+    }
+
+    this.host.nativeElement.classList.add(animationClass);
+    this.appliedClasses.add(animationClass);
+  }
+
+  private applyTextOverride(): void {
+    const definition = this.registry.getDefinition(this.themeKey());
+    const textTarget = this.host.nativeElement.querySelector<HTMLElement>('[data-theme-slot="text"]');
+
+    if (!definition?.supportsTextOverride || !textTarget) {
+      return;
+    }
+
+    if (!this.originalTextContent.has(textTarget)) {
+      this.originalTextContent.set(textTarget, textTarget.textContent ?? '');
+    }
+
+    textTarget.textContent = this.theme.getTextOverride(this.themeKey()) ?? this.originalTextContent.get(textTarget) ?? '';
+  }
+
+  private applyIconOverride(): void {
+    const definition = this.registry.getDefinition(this.themeKey());
+    const iconTarget = this.host.nativeElement.querySelector<HTMLElement>('[data-theme-slot="icon"]');
+    const iconValue = this.theme.getIcon(this.themeKey());
+
+    if (!definition?.supportsIcon || !iconTarget) {
+      return;
+    }
+
+    if (!iconValue) {
+      this.resetIconTarget();
+      return;
+    }
+
+    iconTarget.dataset['themeVisible'] = 'true';
+
+    if (looksLikeImageReference(iconValue)) {
+      const imageReference = iconValue.startsWith('url(')
+        ? iconValue
+        : `url('${iconValue}')`;
+
+      iconTarget.style.backgroundImage = imageReference;
+      iconTarget.textContent = '';
+    } else {
+      iconTarget.style.backgroundImage = 'none';
+      iconTarget.textContent = iconValue.slice(0, 2).toUpperCase();
+    }
+  }
+
+  private applyLinkState(): void {
+    const definition = this.registry.getDefinition(this.themeKey());
+    const link = this.theme.getLink(this.themeKey());
+    const supportsLink = definition?.supportsLink && !!link;
+
+    this.host.nativeElement.dataset['themeLinked'] = supportsLink ? 'true' : 'false';
+
+    if (!supportsLink) {
+      this.host.nativeElement.removeAttribute('tabindex');
+      this.host.nativeElement.removeAttribute('role');
+      return;
+    }
+
+    this.host.nativeElement.setAttribute('tabindex', '0');
+    this.host.nativeElement.setAttribute('role', 'link');
+  }
+
+  private applyPickerState(): void {
+    const definition = this.registry.getDefinition(this.themeKey());
+    const isHovered = this.picker.hoveredKey() === this.themeKey();
+    const isSelected = this.picker.selectedKey() === this.themeKey();
+    const isActive = this.picker.isPicking() && !!definition?.pickerVisible;
+
+    this.host.nativeElement.dataset['themePickerActive'] = isActive ? 'true' : 'false';
+    this.host.nativeElement.dataset['themePickerHovered'] = isHovered ? 'true' : 'false';
+    this.host.nativeElement.dataset['themePickerSelected'] = isSelected ? 'true' : 'false';
+  }
+
+  private openConfiguredLink(event: Event): void {
+    if (this.picker.isPicking()) {
+      return;
+    }
+
+    const definition = this.registry.getDefinition(this.themeKey());
+    const link = this.theme.getLink(this.themeKey());
+
+    if (!definition?.supportsLink || !link) {
+      return;
+    }
+
+    const target = event.target;
+
+    if (target instanceof Element && target.closest('button, input, textarea, select, a, [role="button"]')) {
+      return;
+    }
+
+    event.preventDefault();
+    event.stopPropagation();
+    this.externalLinks.open(link);
+  }
+
+  private clearAppliedStyles(): void {
+    for (const styleKey of this.appliedStyleKeys) {
+      this.host.nativeElement.style.removeProperty(styleKey);
+    }
+
+    this.appliedStyleKeys.clear();
+  }
+
+  private clearAppliedClasses(): void {
+    for (const className of this.appliedClasses) {
+      this.host.nativeElement.classList.remove(className);
+    }
+
+    this.appliedClasses.clear();
+  }
+
+  private restoreTextTarget(): void {
+    const textTarget = this.host.nativeElement.querySelector<HTMLElement>('[data-theme-slot="text"]');
+
+    if (!textTarget || !this.originalTextContent.has(textTarget)) {
+      return;
+    }
+
+    textTarget.textContent = this.originalTextContent.get(textTarget) ?? '';
+  }
+
+  private resetIconTarget(): void {
+    const iconTarget = this.host.nativeElement.querySelector<HTMLElement>('[data-theme-slot="icon"]');
+
+    if (!iconTarget) {
+      return;
+    }
+
+    iconTarget.dataset['themeVisible'] = 'false';
+    iconTarget.style.backgroundImage = 'none';
+    iconTarget.textContent = '';
+  }
+}
\ No newline at end of file
diff --git a/toju-app/src/app/domains/theme/feature/theme-picker-overlay.component.ts b/toju-app/src/app/domains/theme/feature/theme-picker-overlay.component.ts
new file mode 100644
index 0000000..aafd905
--- /dev/null
+++ b/toju-app/src/app/domains/theme/feature/theme-picker-overlay.component.ts
@@ -0,0 +1,58 @@
+import {
+  Component,
+  computed,
+  inject
+} from '@angular/core';
+import { CommonModule } from '@angular/common';
+
+import { ElementPickerService } from '../application/element-picker.service';
+import { ThemeRegistryService } from '../application/theme-registry.service';
+
+@Component({
+  selector: 'app-theme-picker-overlay',
+  standalone: true,
+  imports: [CommonModule],
+  template: `
+    @if (picker.isPicking()) {
+      <div class="pointer-events-none fixed inset-x-0 bottom-4 z-[95] flex justify-center px-4">
+        <div class="pointer-events-auto max-w-xl rounded-2xl border border-border bg-card/95 px-4 py-3 shadow-2xl backdrop-blur-xl">
+          <div class="flex flex-wrap items-center gap-3">
+            <div class="min-w-0 flex-1">
+              <p class="text-xs font-semibold uppercase tracking-[0.18em] text-primary">Theme Picker Active</p>
+              <p class="mt-1 text-sm text-foreground">
+                Click a highlighted area to inspect its theme key.
+              </p>
+              <p class="mt-1 text-xs text-muted-foreground">
+                Hovering:
+                <span class="font-medium text-foreground">{{ hoveredEntry()?.label || 'Move over a themeable region' }}</span>
+                @if (hoveredEntry()) {
+                  <span class="ml-1 rounded-full bg-secondary px-2 py-0.5 font-mono text-[11px] text-foreground/80">{{ hoveredEntry()!.key }}</span>
+                }
+              </p>
+            </div>
+
+            <button
+              type="button"
+              (click)="cancel()"
+              class="inline-flex items-center rounded-full border border-border bg-secondary px-3 py-2 text-sm font-medium text-foreground transition-colors hover:bg-secondary/80"
+            >
+              Cancel
+            </button>
+          </div>
+        </div>
+      </div>
+    }
+  `
+})
+export class ThemePickerOverlayComponent {
+  readonly picker = inject(ElementPickerService);
+  private readonly registry = inject(ThemeRegistryService);
+
+  readonly hoveredEntry = computed(() => {
+    return this.registry.getDefinition(this.picker.hoveredKey());
+  });
+
+  cancel(): void {
+    this.picker.cancel();
+  }
+}
\ No newline at end of file
diff --git a/toju-app/src/app/domains/theme/index.ts b/toju-app/src/app/domains/theme/index.ts
new file mode 100644
index 0000000..014614a
--- /dev/null
+++ b/toju-app/src/app/domains/theme/index.ts
@@ -0,0 +1,13 @@
+export * from './application/theme.service';
+export * from './application/theme-library.service';
+export * from './application/theme-registry.service';
+export * from './application/element-picker.service';
+export * from './application/layout-sync.service';
+export * from './domain/theme.models';
+export * from './domain/theme.defaults';
+export * from './domain/theme.registry';
+export * from './domain/theme.schema';
+export * from './domain/theme.validation';
+
+export { ThemeNodeDirective } from './feature/theme-node.directive';
+export { ThemePickerOverlayComponent } from './feature/theme-picker-overlay.component';
\ No newline at end of file
diff --git a/toju-app/src/app/domains/theme/infrastructure/theme-library.storage.ts b/toju-app/src/app/domains/theme/infrastructure/theme-library.storage.ts
new file mode 100644
index 0000000..639ea39
--- /dev/null
+++ b/toju-app/src/app/domains/theme/infrastructure/theme-library.storage.ts
@@ -0,0 +1,221 @@
+import { Injectable, inject } from '@angular/core';
+import { ElectronBridgeService } from '../../../core/platform/electron/electron-bridge.service';
+import type { SavedThemeFileDescriptor } from '../../../core/platform/electron/electron-api.models';
+import type { SavedThemeSummary } from '../domain/theme.models';
+import { validateThemeDocument } from '../domain/theme.validation';
+
+const THEME_LIBRARY_REQUEST_TIMEOUT_MS = 4000;
+
+function sanitizeSavedThemeStem(value: string): string {
+  const normalized = value
+    .trim()
+    .toLowerCase()
+    .replace(/[^a-z0-9]+/g, '-')
+    .replace(/^-+|-+$/g, '');
+
+  return normalized.length > 0
+    ? normalized
+    : 'theme';
+}
+
+function buildSavedThemeFileName(stem: string, suffix?: number): string {
+  return suffix && suffix > 1
+    ? `${stem}-${suffix}.json`
+    : `${stem}.json`;
+}
+
+function fallbackThemeName(fileName: string): string {
+  return fileName.replace(/\.json$/i, '');
+}
+
+async function withTimeout<T>(operation: Promise<T>, label: string): Promise<T> {
+  let timeoutId: ReturnType<typeof setTimeout> | null = null;
+
+  try {
+    return await Promise.race([
+      operation,
+      new Promise<T>((_resolve, reject) => {
+        timeoutId = setTimeout(() => {
+          reject(new Error(`${label} timed out.`));
+        }, THEME_LIBRARY_REQUEST_TIMEOUT_MS);
+      })
+    ]);
+  } finally {
+    if (timeoutId) {
+      clearTimeout(timeoutId);
+    }
+  }
+}
+
+@Injectable({ providedIn: 'root' })
+export class ThemeLibraryStorageService {
+  private readonly electronBridge = inject(ElectronBridgeService);
+
+  get isAvailable(): boolean {
+    return this.electronBridge.isAvailable;
+  }
+
+  async getSavedThemesPath(): Promise<string | null> {
+    const electronApi = this.electronBridge.getApi();
+
+    if (!electronApi) {
+      return null;
+    }
+
+    try {
+      return await withTimeout(electronApi.getSavedThemesPath(), 'Loading the saved themes path');
+    } catch {
+      return null;
+    }
+  }
+
+  async listThemes(): Promise<SavedThemeSummary[]> {
+    const electronApi = this.electronBridge.getApi();
+
+    if (!electronApi) {
+      return [];
+    }
+
+    try {
+      const files = await withTimeout(electronApi.listSavedThemes(), 'Loading saved themes');
+      const summaries = await Promise.all(files.map(async (file) => await this.readSavedThemeSummary(file)));
+
+      return summaries.sort((left, right) => {
+        const nameOrder = left.themeName.localeCompare(right.themeName, undefined, { sensitivity: 'base' });
+
+        return nameOrder !== 0
+          ? nameOrder
+          : right.modifiedAt - left.modifiedAt;
+      });
+    } catch {
+      return [];
+    }
+  }
+
+  async readThemeText(fileName: string): Promise<string | null> {
+    const electronApi = this.electronBridge.getApi();
+
+    if (!electronApi) {
+      return null;
+    }
+
+    try {
+      return await withTimeout(electronApi.readSavedTheme(fileName), `Reading saved theme ${fileName}`);
+    } catch {
+      return null;
+    }
+  }
+
+  async saveNewTheme(preferredName: string, text: string): Promise<string | null> {
+    const electronApi = this.electronBridge.getApi();
+
+    if (!electronApi) {
+      return null;
+    }
+
+    try {
+      const existingFiles = await withTimeout(electronApi.listSavedThemes(), 'Loading saved themes');
+      const existingNames = new Set(existingFiles.map((file) => file.fileName.toLowerCase()));
+      const stem = sanitizeSavedThemeStem(preferredName);
+
+      let suffix = 1;
+      let fileName = buildSavedThemeFileName(stem);
+
+      while (existingNames.has(fileName.toLowerCase())) {
+        suffix += 1;
+        fileName = buildSavedThemeFileName(stem, suffix);
+      }
+
+      await withTimeout(electronApi.writeSavedTheme(fileName, text), `Saving theme ${fileName}`);
+
+      return fileName;
+    } catch {
+      return null;
+    }
+  }
+
+  async overwriteTheme(fileName: string, text: string): Promise<boolean> {
+    const electronApi = this.electronBridge.getApi();
+
+    if (!electronApi) {
+      return false;
+    }
+
+    try {
+      return await withTimeout(electronApi.writeSavedTheme(fileName, text), `Saving theme ${fileName}`);
+    } catch {
+      return false;
+    }
+  }
+
+  async deleteTheme(fileName: string): Promise<boolean> {
+    const electronApi = this.electronBridge.getApi();
+
+    if (!electronApi) {
+      return false;
+    }
+
+    try {
+      return await withTimeout(electronApi.deleteSavedTheme(fileName), `Deleting theme ${fileName}`);
+    } catch {
+      return false;
+    }
+  }
+
+  private async readSavedThemeSummary(file: SavedThemeFileDescriptor): Promise<SavedThemeSummary> {
+    const text = await this.readThemeText(file.fileName);
+
+    if (!text) {
+      return {
+        description: null,
+        error: 'File could not be read.',
+        fileName: file.fileName,
+        filePath: file.path,
+        isValid: false,
+        modifiedAt: file.modifiedAt,
+        themeName: fallbackThemeName(file.fileName),
+        version: null
+      };
+    }
+
+    try {
+      const parsed = JSON.parse(text) as unknown;
+      const result = validateThemeDocument(parsed);
+
+      if (!result.valid || !result.value) {
+        return {
+          description: null,
+          error: result.errors[0] ?? 'Theme JSON is invalid.',
+          fileName: file.fileName,
+          filePath: file.path,
+          isValid: false,
+          modifiedAt: file.modifiedAt,
+          themeName: fallbackThemeName(file.fileName),
+          version: null
+        };
+      }
+
+      return {
+        description: result.value.meta.description ?? null,
+        error: null,
+        fileName: file.fileName,
+        filePath: file.path,
+        isValid: true,
+        modifiedAt: file.modifiedAt,
+        themeName: result.value.meta.name,
+        version: result.value.meta.version,
+      };
+    } catch (error) {
+      return {
+        description: null,
+        error: error instanceof Error ? error.message : 'Theme JSON could not be parsed.',
+        fileName: file.fileName,
+        filePath: file.path,
+        isValid: false,
+        modifiedAt: file.modifiedAt,
+        themeName: fallbackThemeName(file.fileName),
+        version: null
+      };
+    }
+  }
+}
\ No newline at end of file
diff --git a/toju-app/src/app/domains/theme/infrastructure/theme.storage.ts b/toju-app/src/app/domains/theme/infrastructure/theme.storage.ts
new file mode 100644
index 0000000..e36032d
--- /dev/null
+++ b/toju-app/src/app/domains/theme/infrastructure/theme.storage.ts
@@ -0,0 +1,44 @@
+import {
+  STORAGE_KEY_THEME_ACTIVE,
+  STORAGE_KEY_THEME_DRAFT
+} from '../../../core/constants';
+
+export interface ThemeStorageSnapshot {
+  activeText: string | null;
+  draftText: string | null;
+}
+
+function readStoredThemeText(key: string): string | null {
+  try {
+    const raw = localStorage.getItem(key);
+
+    return typeof raw === 'string' && raw.length > 0
+      ? raw
+      : null;
+  } catch {
+    return null;
+  }
+}
+
+function writeStoredThemeText(key: string, value: string): void {
+  try {
+    localStorage.setItem(key, value);
+  } catch {
+    /* storage can be unavailable in private contexts */
+  }
+}
+
+export function loadThemeStorageSnapshot(): ThemeStorageSnapshot {
+  return {
+    activeText: readStoredThemeText(STORAGE_KEY_THEME_ACTIVE),
+    draftText: readStoredThemeText(STORAGE_KEY_THEME_DRAFT)
+  };
+}
+
+export function saveActiveThemeText(text: string): void {
+  writeStoredThemeText(STORAGE_KEY_THEME_ACTIVE, text);
+}
+
+export function saveDraftThemeText(text: string): void {
+  writeStoredThemeText(STORAGE_KEY_THEME_DRAFT, text);
+}
\ No newline at end of file
diff --git a/toju-app/src/app/domains/voice-session/feature/floating-voice-controls/floating-voice-controls.component.html b/toju-app/src/app/domains/voice-session/feature/floating-voice-controls/floating-voice-controls.component.html
index 232c8cc..083bd40 100644
--- a/toju-app/src/app/domains/voice-session/feature/floating-voice-controls/floating-voice-controls.component.html
+++ b/toju-app/src/app/domains/voice-session/feature/floating-voice-controls/floating-voice-controls.component.html
@@ -1,5 +1,8 @@
 @if (showFloatingControls()) {
-  <div class="fixed bottom-4 right-4 z-50 border border-border bg-card shadow-lg">
+  <div
+    appThemeNode="floatingVoiceControls"
+    class="fixed bottom-4 right-4 z-50 border border-border bg-card shadow-lg"
+  >
     <div class="flex items-center gap-2 p-2">
       <!-- Back to server button -->
       <button
diff --git a/toju-app/src/app/domains/voice-session/feature/floating-voice-controls/floating-voice-controls.component.ts b/toju-app/src/app/domains/voice-session/feature/floating-voice-controls/floating-voice-controls.component.ts
index 4813e3e..c7f768b 100644
--- a/toju-app/src/app/domains/voice-session/feature/floating-voice-controls/floating-voice-controls.component.ts
+++ b/toju-app/src/app/domains/voice-session/feature/floating-voice-controls/floating-voice-controls.component.ts
@@ -27,6 +27,7 @@ import { ScreenShareFacade, ScreenShareQuality } from '../../../../domains/scree
 import { UsersActions } from '../../../../store/users/users.actions';
 import { selectCurrentUser } from '../../../../store/users/users.selectors';
 import { DebugConsoleComponent, ScreenShareQualityDialogComponent } from '../../../../shared';
+import { ThemeNodeDirective } from '../../../../domains/theme';
 
 @Component({
   selector: 'app-floating-voice-controls',
@@ -35,7 +36,8 @@ import { DebugConsoleComponent, ScreenShareQualityDialogComponent } from '../../
     CommonModule,
     NgIcon,
     DebugConsoleComponent,
-    ScreenShareQualityDialogComponent
+    ScreenShareQualityDialogComponent,
+    ThemeNodeDirective
   ],
   viewProviders: [
     provideIcons({
diff --git a/toju-app/src/app/domains/voice-session/feature/voice-controls/voice-controls.component.html b/toju-app/src/app/domains/voice-session/feature/voice-controls/voice-controls.component.html
index 027c762..cd5fe0b 100644
--- a/toju-app/src/app/domains/voice-session/feature/voice-controls/voice-controls.component.html
+++ b/toju-app/src/app/domains/voice-session/feature/voice-controls/voice-controls.component.html
@@ -1,7 +1,4 @@
-<div
-  class="flex flex-col rounded-md border border-border bg-background px-3 py-2.5"
-  [style.height]="showConnectionError() ? null : 'calc(100px - 0.75rem)'"
->
+<div class="flex flex-col rounded-md border border-border bg-background px-3 py-2.5">
   <!-- Connection Error Banner -->
   @if (showConnectionError()) {
     <div class="mb-3 flex items-center gap-2 rounded-md border border-destructive/30 bg-destructive/10 p-2">
@@ -18,7 +15,7 @@
   }
 
   <!-- User Info -->
-  <div class="mb-2 flex items-center gap-3">
+  <div class="flex items-center gap-3">
     <app-user-avatar
       [name]="currentUser()?.displayName || '?'"
       size="sm"
@@ -56,89 +53,100 @@
   </div>
 
   <!-- Voice Controls -->
-  <div class="mt-auto flex items-center justify-center gap-2">
-    @if (isConnected()) {
-      <!-- Mute Toggle -->
-      <button
-        type="button"
-        (click)="toggleMute()"
-        [class]="getMuteButtonClass()"
-      >
-        @if (isMuted()) {
-          <ng-icon
-            name="lucideMicOff"
-            class="w-5 h-5"
-          />
-        } @else {
-          <ng-icon
-            name="lucideMic"
-            class="w-5 h-5"
-          />
-        }
-      </button>
+  <div
+    class="grid overflow-hidden duration-200 ease-out motion-reduce:transition-none"
+    style="transition-property: grid-template-rows, opacity, margin-top"
+    [style.gridTemplateRows]="isConnected() ? '1fr' : '0fr'"
+    [style.opacity]="isConnected() ? '1' : '0'"
+    [style.marginTop.rem]="isConnected() ? 0.5 : 0"
+    [style.visibility]="isConnected() ? 'visible' : 'hidden'"
+    [class.pointer-events-none]="!isConnected()"
+    [attr.aria-hidden]="isConnected() ? null : 'true'"
+  >
+    <div class="overflow-hidden">
+      <div class="flex items-center justify-center gap-2">
+        <!-- Mute Toggle -->
+        <button
+          type="button"
+          (click)="toggleMute()"
+          [class]="getMuteButtonClass()"
+        >
+          @if (isMuted()) {
+            <ng-icon
+              name="lucideMicOff"
+              class="w-5 h-5"
+            />
+          } @else {
+            <ng-icon
+              name="lucideMic"
+              class="w-5 h-5"
+            />
+          }
+        </button>
 
-      <!-- Deafen Toggle -->
-      <button
-        type="button"
-        (click)="toggleDeafen()"
-        [class]="getDeafenButtonClass()"
-      >
-        <ng-icon
-          name="lucideHeadphones"
-          class="w-5 h-5"
-        />
-      </button>
+        <!-- Deafen Toggle -->
+        <button
+          type="button"
+          (click)="toggleDeafen()"
+          [class]="getDeafenButtonClass()"
+        >
+          <ng-icon
+            name="lucideHeadphones"
+            class="w-5 h-5"
+          />
+        </button>
 
-      <!-- Camera Toggle -->
-      <button
-        type="button"
-        (click)="toggleCamera()"
-        [class]="getCameraButtonClass()"
-      >
-        @if (isCameraEnabled()) {
-          <ng-icon
-            name="lucideVideoOff"
-            class="w-5 h-5"
-          />
-        } @else {
-          <ng-icon
-            name="lucideVideo"
-            class="w-5 h-5"
-          />
-        }
-      </button>
+        <!-- Camera Toggle -->
+        <button
+          type="button"
+          (click)="toggleCamera()"
+          [class]="getCameraButtonClass()"
+        >
+          @if (isCameraEnabled()) {
+            <ng-icon
+              name="lucideVideoOff"
+              class="w-5 h-5"
+            />
+          } @else {
+            <ng-icon
+              name="lucideVideo"
+              class="w-5 h-5"
+            />
+          }
+        </button>
 
-      <!-- Screen Share Toggle -->
-      <button
-        type="button"
-        (click)="toggleScreenShare()"
-        [class]="getScreenShareButtonClass()"
-      >
-        @if (isScreenSharing()) {
-          <ng-icon
-            name="lucideMonitorOff"
-            class="w-5 h-5"
-          />
-        } @else {
-          <ng-icon
-            name="lucideMonitor"
-            class="w-5 h-5"
-          />
-        }
-      </button>
+        <!-- Screen Share Toggle -->
+        <button
+          type="button"
+          (click)="toggleScreenShare()"
+          [class]="getScreenShareButtonClass()"
+        >
+          @if (isScreenSharing()) {
+            <ng-icon
+              name="lucideMonitorOff"
+              class="w-5 h-5"
+            />
+          } @else {
+            <ng-icon
+              name="lucideMonitor"
+              class="w-5 h-5"
+            />
+          }
+        </button>
 
-      <!-- Disconnect -->
-      <button
-        type="button"
-        (click)="disconnect()"
-        class="inline-flex h-10 w-10 items-center justify-center rounded-md border border-destructive/20 bg-destructive/10 text-destructive transition-colors hover:bg-destructive/15"
-      >
-        <ng-icon
-          name="lucidePhoneOff"
-          class="w-5 h-5"
-        />
-      </button>
-    }
+        <!-- Disconnect -->
+        <button
+          type="button"
+          (click)="disconnect()"
+          class="inline-flex h-10 w-10 items-center justify-center rounded-md border border-destructive/20 bg-destructive/10 text-destructive transition-colors hover:bg-destructive/15"
+        >
+          <ng-icon
+            name="lucidePhoneOff"
+            class="w-5 h-5"
+          />
+        </button>
+      </div>
+    </div>
   </div>
 </div>
 
diff --git a/toju-app/src/app/features/room/chat-room/chat-room.component.html b/toju-app/src/app/features/room/chat-room/chat-room.component.html
index 7cfc546..f89f591 100644
--- a/toju-app/src/app/features/room/chat-room/chat-room.component.html
+++ b/toju-app/src/app/features/room/chat-room/chat-room.component.html
@@ -1,29 +1,50 @@
 <div class="flex h-full flex-col bg-background">
   @if (currentRoom()) {
-    <!-- Main Content -->
-    <div class="flex min-h-0 flex-1 overflow-hidden">
-      <aside class="flex min-h-0 w-[17rem] shrink-0 overflow-hidden border-r border-border bg-card">
+    <div
+      class="grid min-h-0 flex-1 overflow-hidden"
+      [ngStyle]="roomLayoutStyles()"
+    >
+      <aside
+        appThemeNode="chatRoomChannelsPanel"
+        class="flex min-h-0 overflow-hidden border-r border-border bg-card"
+        [ngStyle]="channelsPanelLayoutStyles()"
+      >
         <app-rooms-side-panel
           panelMode="channels"
           class="block h-full w-full"
         />
       </aside>
 
-      <!-- Chat Area -->
-      <main class="relative min-h-0 min-w-0 flex-1 overflow-hidden bg-background">
+      <main
+        appThemeNode="chatRoomMainPanel"
+        class="relative min-h-0 min-w-0 overflow-hidden bg-background"
+        [ngStyle]="mainPanelLayoutStyles()"
+      >
         @if (!isVoiceWorkspaceExpanded()) {
           @if (hasTextChannels()) {
             <div class="h-full overflow-hidden">
               <app-chat-messages />
             </div>
           } @else {
-            <div class="flex h-full items-center justify-center px-6">
+            <div
+              appThemeNode="chatRoomEmptyState"
+              class="flex h-full items-center justify-center px-6"
+            >
               <div class="max-w-md text-center text-muted-foreground">
+                <div
+                  data-theme-slot="icon"
+                  class="theme-icon-slot mx-auto mb-4 h-14 w-14 items-center justify-center rounded-3xl border border-border/70 bg-secondary/70 bg-center bg-cover bg-no-repeat text-sm font-semibold uppercase tracking-[0.18em] text-foreground"
+                ></div>
                 <ng-icon
                   name="lucideHash"
                   class="mx-auto mb-4 h-16 w-16 opacity-30"
                 />
-                <h2 class="mb-2 text-xl font-medium text-foreground">No text channels</h2>
+                <h2
+                  data-theme-slot="text"
+                  class="mb-2 text-xl font-medium text-foreground"
+                >
+                  No text channels
+                </h2>
                 <p class="text-sm">There are no existing text channels currently.</p>
               </div>
             </div>
@@ -33,7 +54,11 @@
         <app-voice-workspace />
       </main>
 
-      <aside class="flex min-h-0 w-[17rem] shrink-0 overflow-hidden border-l border-border bg-card">
+      <aside
+        appThemeNode="chatRoomMembersPanel"
+        class="flex min-h-0 overflow-hidden border-l border-border bg-card"
+        [ngStyle]="membersPanelLayoutStyles()"
+      >
         <app-rooms-side-panel
           panelMode="users"
           [showVoiceControls]="false"
@@ -42,14 +67,25 @@
       </aside>
     </div>
   } @else {
-    <!-- No Room Selected -->
-    <div class="flex flex-1 items-center justify-center bg-background px-6">
+    <div
+      appThemeNode="chatRoomEmptyState"
+      class="flex flex-1 items-center justify-center bg-background px-6"
+    >
       <div class="text-center text-muted-foreground">
+        <div
+          data-theme-slot="icon"
+          class="theme-icon-slot mx-auto mb-4 h-14 w-14 items-center justify-center rounded-3xl border border-border/70 bg-secondary/70 bg-center bg-cover bg-no-repeat text-sm font-semibold uppercase tracking-[0.18em] text-foreground"
+        ></div>
         <ng-icon
           name="lucideHash"
           class="mx-auto mb-4 h-16 w-16 opacity-30"
         />
-        <h2 class="mb-2 text-xl font-medium">No room selected</h2>
+        <h2
+          data-theme-slot="text"
+          class="mb-2 text-xl font-medium"
+        >
+          No room selected
+        </h2>
         <p class="text-sm">Select or create a room to start chatting</p>
       </div>
     </div>
diff --git a/toju-app/src/app/features/room/chat-room/chat-room.component.ts b/toju-app/src/app/features/room/chat-room/chat-room.component.ts
index 3318796..b98123c 100644
--- a/toju-app/src/app/features/room/chat-room/chat-room.component.ts
+++ b/toju-app/src/app/features/room/chat-room/chat-room.component.ts
@@ -29,6 +29,10 @@ import {
 import { SettingsModalService } from '../../../core/services/settings-modal.service';
 import { selectIsCurrentUserAdmin } from '../../../store/users/users.selectors';
 import { VoiceWorkspaceService } from '../../../domains/voice-session';
+import {
+  ThemeNodeDirective,
+  ThemeService
+} from '../../../domains/theme';
 
 @Component({
   selector: 'app-chat-room',
@@ -38,7 +42,8 @@ import { VoiceWorkspaceService } from '../../../domains/voice-session';
     NgIcon,
     ChatMessagesComponent,
     VoiceWorkspaceComponent,
-    RoomsSidePanelComponent
+    RoomsSidePanelComponent,
+    ThemeNodeDirective
   ],
   viewProviders: [
     provideIcons({
@@ -59,6 +64,7 @@ import { VoiceWorkspaceService } from '../../../domains/voice-session';
 export class ChatRoomComponent {
   private readonly store = inject(Store);
   private readonly settingsModal = inject(SettingsModalService);
+  private readonly theme = inject(ThemeService);
   private voiceWorkspace = inject(VoiceWorkspaceService);
   showMenu = signal(false);
   showAdminPanel = signal(false);
@@ -68,6 +74,10 @@ export class ChatRoomComponent {
   textChannels = this.store.selectSignal(selectTextChannels);
   isVoiceWorkspaceExpanded = this.voiceWorkspace.isExpanded;
   hasTextChannels = computed(() => this.textChannels().length > 0);
+  roomLayoutStyles = computed(() => this.theme.getLayoutContainerStyles('roomLayout'));
+  channelsPanelLayoutStyles = computed(() => this.theme.getLayoutItemStyles('chatRoomChannelsPanel'));
+  mainPanelLayoutStyles = computed(() => this.theme.getLayoutItemStyles('chatRoomMainPanel'));
+  membersPanelLayoutStyles = computed(() => this.theme.getLayoutItemStyles('chatRoomMembersPanel'));
 
   /** Open the settings modal to the Server admin page for the current room. */
   toggleAdminPanel() {
diff --git a/toju-app/src/app/features/room/voice-workspace/voice-workspace.component.html b/toju-app/src/app/features/room/voice-workspace/voice-workspace.component.html
index 8e604d4..3858b2f 100644
--- a/toju-app/src/app/features/room/voice-workspace/voice-workspace.component.html
+++ b/toju-app/src/app/features/room/voice-workspace/voice-workspace.component.html
@@ -2,6 +2,7 @@
 <div class="absolute inset-0">
   @if (showExpanded()) {
     <section
+      appThemeNode="voiceWorkspace"
       class="pointer-events-auto absolute inset-0 bg-background/95 backdrop-blur-xl"
       (mouseenter)="onWorkspacePointerMove()"
       (mousemove)="onWorkspacePointerMove()"
@@ -276,6 +277,7 @@
 
   @if (showMiniWindow()) {
     <div
+      appThemeNode="voiceWorkspace"
       class="pointer-events-auto absolute z-20 w-[20rem] select-none overflow-hidden rounded-[1.75rem] border border-white/10 bg-card/95 shadow-2xl backdrop-blur-xl"
       [style.left.px]="miniPosition().left"
       [style.top.px]="miniPosition().top"
diff --git a/toju-app/src/app/features/room/voice-workspace/voice-workspace.component.ts b/toju-app/src/app/features/room/voice-workspace/voice-workspace.component.ts
index 8eb9717..863b3f3 100644
--- a/toju-app/src/app/features/room/voice-workspace/voice-workspace.component.ts
+++ b/toju-app/src/app/features/room/voice-workspace/voice-workspace.component.ts
@@ -50,6 +50,7 @@ import { ScreenShareQualityDialogComponent, UserAvatarComponent } from '../../..
 import { VoiceWorkspacePlaybackService } from './voice-workspace-playback.service';
 import { VoiceWorkspaceStreamTileComponent } from './voice-workspace-stream-tile.component';
 import { VoiceWorkspaceStreamItem } from './voice-workspace.models';
+import { ThemeNodeDirective } from '../../../domains/theme';
 
 @Component({
   selector: 'app-voice-workspace',
@@ -59,7 +60,8 @@ import { VoiceWorkspaceStreamItem } from './voice-workspace.models';
     NgIcon,
     ScreenShareQualityDialogComponent,
     VoiceWorkspaceStreamTileComponent,
-    UserAvatarComponent
+    UserAvatarComponent,
+    ThemeNodeDirective
   ],
   viewProviders: [
     provideIcons({
diff --git a/toju-app/src/app/features/settings/settings-modal/settings-modal.component.html b/toju-app/src/app/features/settings/settings-modal/settings-modal.component.html
index 7f73b80..1b41230 100644
--- a/toju-app/src/app/features/settings/settings-modal/settings-modal.component.html
+++ b/toju-app/src/app/features/settings/settings-modal/settings-modal.component.html
@@ -1,5 +1,5 @@
 <!-- eslint-disable @angular-eslint/template/cyclomatic-complexity -->
-@if (isOpen()) {
+@if (isOpen() && !isThemeStudioFullscreen()) {
   <!-- Backdrop -->
   <div
     class="fixed inset-0 z-[90] bg-black/80 backdrop-blur-sm transition-opacity duration-200"
@@ -16,7 +16,8 @@
   <!-- Modal -->
   <div class="fixed inset-0 z-[91] flex items-center justify-center p-4 pointer-events-none">
     <div
-      class="pointer-events-auto relative bg-card border border-border rounded-xl shadow-2xl w-full max-w-4xl h-[min(680px,85vh)] flex overflow-hidden transition-all duration-200"
+      class="pointer-events-auto relative flex w-full max-w-4xl overflow-hidden rounded-xl border border-border bg-card shadow-2xl transition-all duration-200"
+      style="height: min(680px, 85vh)"
       [class.scale-100]="animating()"
       [class.opacity-100]="animating()"
       [class.scale-95]="!animating()"
@@ -29,7 +30,7 @@
       tabindex="-1"
     >
       <!-- Side Navigation -->
-      <nav class="w-52 flex-shrink-0 bg-secondary/40 border-r border-border flex flex-col">
+      <nav class="flex w-52 flex-shrink-0 flex-col border-r border-border bg-secondary/40">
         <div class="p-4 border-b border-border">
           <h2 class="text-lg font-semibold text-foreground">Settings</h2>
         </div>
@@ -99,7 +100,15 @@
           }
         </div>
 
-        <div class="mt-auto border-t border-border px-4 py-3">
+        <div class="mt-auto space-y-3 border-t border-border px-4 py-3">
+          <button
+            type="button"
+            (click)="restoreDefaultTheme()"
+            class="w-full rounded-lg border border-destructive/25 bg-destructive/10 px-3 py-2 text-left text-xs font-medium text-destructive transition-colors hover:bg-destructive/15"
+          >
+            Restore default theme
+          </button>
+
           <button
             type="button"
             (click)="openThirdPartyLicenses()"
@@ -122,6 +131,9 @@
               @case ('network') {
                 Network
               }
+              @case ('theme') {
+                Theme Studio
+              }
               @case ('notifications') {
                 Notifications
               }
@@ -148,16 +160,18 @@
               }
             }
           </h3>
-          <button
-            (click)="close()"
-            type="button"
-            class="p-2 hover:bg-secondary rounded-lg transition-colors text-muted-foreground hover:text-foreground"
-          >
-            <ng-icon
-              name="lucideX"
-              class="w-5 h-5"
-            />
-          </button>
+          <div class="flex items-center gap-2">
+            <button
+              (click)="close()"
+              type="button"
+              class="p-2 hover:bg-secondary rounded-lg transition-colors text-muted-foreground hover:text-foreground"
+            >
+              <ng-icon
+                name="lucideX"
+                class="w-5 h-5"
+              />
+            </button>
+          </div>
         </div>
 
         <!-- Scrollable Content Area -->
@@ -169,6 +183,74 @@
             @case ('network') {
               <app-network-settings />
             }
+            @case ('theme') {
+              <div class="mx-auto flex h-full max-w-3xl items-center justify-center">
+                <div class="w-full rounded-[1.5rem] border border-border bg-card/90 p-6 shadow-sm">
+                  <div class="flex flex-wrap items-start justify-between gap-4">
+                    <div>
+                      <p class="text-xs font-semibold uppercase tracking-[0.18em] text-primary">Active Theme</p>
+                      <h4 class="mt-2 text-xl font-semibold text-foreground">{{ activeThemeName() }}</h4>
+                    </div>
+
+                    @if (themeStudioMinimized()) {
+                      <span class="rounded-full border border-primary/25 bg-primary/10 px-3 py-1 text-xs font-semibold text-primary">Minimized</span>
+                    }
+                  </div>
+
+                  @if (savedThemesAvailable()) {
+                    <div class="mt-5">
+                      <label class="text-[11px] font-semibold uppercase tracking-[0.18em] text-muted-foreground">Saved Theme</label>
+
+                      <div class="mt-2 flex flex-wrap gap-2">
+                        <select
+                          class="min-w-[16rem] flex-1 rounded-full border border-border bg-background px-3 py-2 text-sm font-medium text-foreground outline-none transition-colors focus:border-primary/40 focus:ring-2 focus:ring-primary/15"
+                          [value]="selectedSavedTheme()?.fileName || ''"
+                          [disabled]="savedThemesBusy() && savedThemes().length === 0"
+                          (change)="onSavedThemeSelect($event)"
+                        >
+                          <option value="">{{ savedThemes().length > 0 ? 'Choose saved theme' : 'No saved themes' }}</option>
+                          @for (savedTheme of savedThemes(); track savedTheme.fileName) {
+                            <option
+                              [value]="savedTheme.fileName"
+                              [disabled]="!savedTheme.isValid"
+                            >
+                              {{ savedTheme.themeName }}
+                            </option>
+                          }
+                        </select>
+
+                        <button
+                          type="button"
+                          (click)="editSelectedSavedTheme()"
+                          [disabled]="!selectedSavedTheme()?.isValid || (savedThemesBusy() && savedThemes().length === 0)"
+                          class="inline-flex items-center rounded-full border border-border bg-background px-3 py-2 text-sm font-medium text-foreground transition-colors hover:bg-secondary disabled:cursor-not-allowed disabled:opacity-60"
+                        >
+                          Edit In Studio
+                        </button>
+                      </div>
+                    </div>
+                  }
+
+                  <div class="mt-5 flex flex-wrap gap-2">
+                    <button
+                      type="button"
+                      (click)="openThemeStudio()"
+                      class="inline-flex items-center rounded-full bg-primary px-4 py-2 text-sm font-semibold text-primary-foreground transition-colors hover:bg-primary/90"
+                    >
+                      {{ themeStudioMinimized() ? 'Re-open Theme Studio' : 'Open Theme Studio' }}
+                    </button>
+
+                    <button
+                      type="button"
+                      (click)="restoreDefaultTheme()"
+                      class="inline-flex items-center rounded-full border border-destructive/25 bg-destructive/10 px-3 py-2 text-sm font-medium text-destructive transition-colors hover:bg-destructive/15"
+                    >
+                      Restore Default
+                    </button>
+                  </div>
+                </div>
+              </div>
+            }
             @case ('notifications') {
               <app-notifications-settings />
             }
diff --git a/toju-app/src/app/features/settings/settings-modal/settings-modal.component.ts b/toju-app/src/app/features/settings/settings-modal/settings-modal.component.ts
index 8c7a6dd..73632e3 100644
--- a/toju-app/src/app/features/settings/settings-modal/settings-modal.component.ts
+++ b/toju-app/src/app/features/settings/settings-modal/settings-modal.component.ts
@@ -5,6 +5,7 @@ import {
   signal,
   computed,
   effect,
+  untracked,
   HostListener,
   viewChild
 } from '@angular/core';
@@ -19,6 +20,7 @@ import {
   lucideDownload,
   lucideGlobe,
   lucideAudioLines,
+  lucidePalette,
   lucideSettings,
   lucideUsers,
   lucideBan,
@@ -43,6 +45,7 @@ import { PermissionsSettingsComponent } from './permissions-settings/permissions
 import { DebuggingSettingsComponent } from './debugging-settings/debugging-settings.component';
 import { UpdatesSettingsComponent } from './updates-settings/updates-settings.component';
 import { THIRD_PARTY_LICENSES, type ThirdPartyLicense } from './third-party-licenses';
+import { ThemeLibraryService, ThemeService } from '../../../domains/theme';
 
 @Component({
   selector: 'app-settings-modal',
@@ -70,6 +73,7 @@ import { THIRD_PARTY_LICENSES, type ThirdPartyLicense } from './third-party-lice
       lucideDownload,
       lucideGlobe,
       lucideAudioLines,
+      lucidePalette,
       lucideSettings,
       lucideUsers,
       lucideBan,
@@ -82,6 +86,8 @@ export class SettingsModalComponent {
   readonly modal = inject(SettingsModalService);
   private store = inject(Store);
   private webrtc = inject(RealtimeSessionFacade);
+  private theme = inject(ThemeService);
+  private themeLibrary = inject(ThemeLibraryService);
   readonly thirdPartyLicenses: readonly ThirdPartyLicense[] = THIRD_PARTY_LICENSES;
   private lastRequestedServerId: string | null = null;
 
@@ -93,11 +99,22 @@ export class SettingsModalComponent {
 
   isOpen = this.modal.isOpen;
   activePage = this.modal.activePage;
+  themeStudioFullscreen = this.modal.themeStudioFullscreen;
+  themeStudioMinimized = this.modal.themeStudioMinimized;
+  isThemeStudioFullscreen = computed(() => this.activePage() === 'theme' && this.themeStudioFullscreen());
+  activeThemeName = this.theme.activeThemeName;
+  savedThemesAvailable = this.themeLibrary.isAvailable;
+  savedThemes = this.themeLibrary.entries;
+  savedThemesBusy = this.themeLibrary.isBusy;
+  selectedSavedTheme = this.themeLibrary.selectedEntry;
 
   readonly globalPages: { id: SettingsPage; label: string; icon: string }[] = [
     { id: 'general',
       label: 'General',
       icon: 'lucideSettings' },
+    { id: 'theme',
+      label: 'Theme Studio',
+      icon: 'lucidePalette' },
     { id: 'network',
       label: 'Network',
       icon: 'lucideGlobe' },
@@ -220,6 +237,16 @@ export class SettingsModalComponent {
       this.animating.set(true);
     });
 
+    effect(() => {
+      if (!this.isOpen() || this.activePage() !== 'theme' || !this.savedThemesAvailable()) {
+        return;
+      }
+
+      untracked(() => {
+        void this.refreshSavedThemes();
+      });
+    });
+
     effect(() => {
       const server = this.selectedServer();
 
@@ -280,6 +307,11 @@ export class SettingsModalComponent {
       return;
     }
 
+    if (this.isThemeStudioFullscreen()) {
+      this.modal.minimizeThemeStudio();
+      return;
+    }
+
     if (this.isOpen()) {
       this.close();
     }
@@ -303,6 +335,40 @@ export class SettingsModalComponent {
     this.modal.navigate(page);
   }
 
+  openThemeStudio(): void {
+    this.modal.openThemeStudio();
+  }
+
+  async refreshSavedThemes(): Promise<void> {
+    await this.themeLibrary.refresh();
+    this.syncSavedThemeSelectionToActiveTheme();
+  }
+
+  async onSavedThemeSelect(event: Event): Promise<void> {
+    const select = event.target as HTMLSelectElement;
+    const fileName = select.value || null;
+
+    this.themeLibrary.select(fileName);
+
+    if (!fileName) {
+      return;
+    }
+
+    const applied = await this.themeLibrary.useSelectedTheme();
+
+    if (!applied) {
+      this.syncSavedThemeSelectionToActiveTheme();
+    }
+  }
+
+  async editSelectedSavedTheme(): Promise<void> {
+    const opened = await this.themeLibrary.openSelectedThemeInDraft();
+
+    if (opened) {
+      this.modal.openThemeStudio();
+    }
+  }
+
   onBackdropClick(): void {
     this.close();
   }
@@ -312,4 +378,16 @@ export class SettingsModalComponent {
 
     this.selectedServerId.set(select.value || null);
   }
+
+  restoreDefaultTheme(): void {
+    this.theme.resetToDefault('button');
+    this.syncSavedThemeSelectionToActiveTheme();
+    this.navigate('theme');
+  }
+
+  private syncSavedThemeSelectionToActiveTheme(): void {
+    const matchingTheme = this.savedThemes().find((entry) => entry.isValid && entry.themeName === this.activeThemeName()) ?? null;
+
+    this.themeLibrary.select(matchingTheme?.fileName ?? null);
+  }
 }
diff --git a/toju-app/src/app/features/shell/title-bar.component.html b/toju-app/src/app/features/shell/title-bar.component.html
index 30f8422..34633f3 100644
--- a/toju-app/src/app/features/shell/title-bar.component.html
+++ b/toju-app/src/app/features/shell/title-bar.component.html
@@ -1,17 +1,38 @@
 <div
-  class="fixed left-16 right-0 top-0 z-50 flex h-10 items-center justify-between border-b border-border bg-card px-4 select-none"
+  appThemeNode="titleBar"
+  class="relative z-50 flex h-10 w-full items-center justify-between border-b border-border bg-card px-4 select-none"
   style="-webkit-app-region: drag"
 >
   <div
     class="flex items-center gap-2 min-w-0 relative"
     style="-webkit-app-region: no-drag"
   >
+    <span
+      data-theme-slot="icon"
+      class="theme-icon-slot h-6 w-6 shrink-0 items-center justify-center rounded-xl border border-border/70 bg-secondary/70 bg-center bg-cover bg-no-repeat text-[10px] font-semibold uppercase tracking-[0.16em] text-foreground"
+    ></span>
+
     @if (inRoom()) {
-      <ng-icon
-        name="lucideHash"
-        class="w-5 h-5 text-muted-foreground"
-      />
-      <span class="truncate text-sm font-semibold text-foreground">{{ roomContextTitle() }}</span>
+      <span
+        data-theme-slot="text"
+        class="flex min-w-0 items-center gap-2 text-sm font-semibold text-foreground"
+      >
+        <span class="truncate">{{ roomName() }}</span>
+
+        @if (isVoiceWorkspaceExpanded()) {
+          <span class="shrink-0 text-muted-foreground">/</span>
+          <span class="truncate">{{ connectedVoiceChannelName() }}</span>
+        } @else if (textChannels().length > 0) {
+          <span class="shrink-0 text-muted-foreground">/</span>
+          <span class="flex min-w-0 items-center gap-1 text-foreground">
+            <ng-icon
+              name="lucideHash"
+              class="h-4 w-4 shrink-0 text-muted-foreground"
+            />
+            <span class="truncate">{{ activeTextChannelName() }}</span>
+          </span>
+        }
+      </span>
 
       @if (showRoomCompatibilityNotice()) {
         <span class="inline-flex items-center gap-1 rounded bg-destructive/15 px-2 py-0.5 text-xs text-destructive">
@@ -36,7 +57,11 @@
       }
     } @else {
       <div class="flex items-center gap-2 min-w-0">
-        <span class="text-sm text-muted-foreground truncate">{{ username() }} | {{ serverName() }}</span>
+        <span
+          data-theme-slot="text"
+          class="text-sm text-muted-foreground truncate"
+          >{{ username() }} | {{ serverName() }}</span
+        >
         <span
           class="text-xs px-2 py-0.5 rounded bg-destructive/15 text-destructive"
           [class.hidden]="!isReconnecting()"
@@ -59,57 +84,62 @@
       Login
     </button>
 
-    <button
-      type="button"
-      (click)="toggleMenu()"
-      class="ml-2 rounded-md p-2 transition-colors hover:bg-secondary"
-      title="Menu"
-    >
-      <ng-icon
-        name="lucideMenu"
-        class="w-5 h-5 text-muted-foreground"
-      />
-    </button>
-    <!-- Anchored dropdown under the menu button -->
-    @if (showMenu()) {
-      <div class="absolute right-0 top-full z-50 mt-2 w-64 rounded-md border border-border bg-popover p-1 shadow-lg">
-        @if (inRoom()) {
-          <button
-            type="button"
-            (click)="createInviteLink()"
-            [disabled]="creatingInvite()"
-            class="w-full rounded-md px-3 py-2 text-left text-sm text-foreground transition-colors hover:bg-secondary disabled:cursor-not-allowed disabled:opacity-60"
+    <div class="relative">
+      <button
+        type="button"
+        (click)="toggleMenu()"
+        class="grid h-8 w-8 place-items-center rounded-md transition-colors hover:bg-secondary"
+        title="Menu"
+      >
+        <ng-icon
+          name="lucideMenu"
+          class="h-4 w-4 text-muted-foreground"
+        />
+      </button>
+
+      @if (showMenu()) {
+        <div
+          class="absolute right-0 top-full z-50 mt-2 w-64 rounded-md border border-border bg-popover p-1 shadow-lg"
+          style="-webkit-app-region: no-drag"
+        >
+          @if (inRoom()) {
+            <button
+              type="button"
+              (click)="createInviteLink()"
+              [disabled]="creatingInvite()"
+              class="w-full rounded-md px-3 py-2 text-left text-sm text-foreground transition-colors hover:bg-secondary disabled:cursor-not-allowed disabled:opacity-60"
+            >
+              @if (creatingInvite()) {
+                Creating Invite Link…
+              } @else {
+                Create Invite Link
+              }
+            </button>
+            <button
+              type="button"
+              (click)="leaveServer()"
+              class="w-full rounded-md px-3 py-2 text-left text-sm text-foreground transition-colors hover:bg-secondary"
+            >
+              Leave Server
+            </button>
+          }
+          <div
+            class="px-3 py-2 text-xs leading-5 text-muted-foreground"
+            [class.hidden]="!inviteStatus()"
           >
-            @if (creatingInvite()) {
-              Creating Invite Link…
-            } @else {
-              Create Invite Link
-            }
-          </button>
+            {{ inviteStatus() }}
+          </div>
+          <div class="mx-2 my-1 h-px bg-border"></div>
           <button
             type="button"
-            (click)="leaveServer()"
+            (click)="logout()"
             class="w-full rounded-md px-3 py-2 text-left text-sm text-foreground transition-colors hover:bg-secondary"
           >
-            Leave Server
+            Logout
           </button>
-        }
-        <div
-          class="px-3 py-2 text-xs leading-5 text-muted-foreground"
-          [class.hidden]="!inviteStatus()"
-        >
-          {{ inviteStatus() }}
         </div>
-        <div class="mx-2 my-1 h-px bg-border"></div>
-        <button
-          type="button"
-          (click)="logout()"
-          class="w-full rounded-md px-3 py-2 text-left text-sm text-foreground transition-colors hover:bg-secondary"
-        >
-          Logout
-        </button>
-      </div>
-    }
+      }
+    </div>
     @if (isElectron()) {
       <button
         type="button"
diff --git a/toju-app/src/app/features/shell/title-bar.component.ts b/toju-app/src/app/features/shell/title-bar.component.ts
index b00acdd..efcab73 100644
--- a/toju-app/src/app/features/shell/title-bar.component.ts
+++ b/toju-app/src/app/features/shell/title-bar.component.ts
@@ -37,6 +37,7 @@ import { STORAGE_KEY_CURRENT_USER_ID } from '../../core/constants';
 import { LeaveServerDialogComponent } from '../../shared';
 import { Room } from '../../shared-kernel';
 import { VoiceWorkspaceService } from '../../domains/voice-session';
+import { ThemeNodeDirective } from '../../domains/theme';
 
 @Component({
   selector: 'app-title-bar',
@@ -44,7 +45,8 @@ import { VoiceWorkspaceService } from '../../domains/voice-session';
   imports: [
     CommonModule,
     NgIcon,
-    LeaveServerDialogComponent
+    LeaveServerDialogComponent,
+    ThemeNodeDirective
   ],
   viewProviders: [
     provideIcons({ lucideMinus,
@@ -109,23 +111,6 @@ export class TitleBarComponent {
 
     return voiceChannel?.name || 'Voice Lounge';
   });
-  roomContextTitle = computed(() => {
-    const room = this.currentRoom();
-
-    if (!room) {
-      return '';
-    }
-
-    if (this.isVoiceWorkspaceExpanded()) {
-      return `${room.name} / ${this.connectedVoiceChannelName()}`;
-    }
-
-    if (this.textChannels().length === 0) {
-      return room.name;
-    }
-
-    return `${room.name} / #${this.activeTextChannelName()}`;
-  });
   roomContextMeta = computed(() => {
     if (!this.currentRoom()) {
       return '';
diff --git a/toju-app/src/styles.scss b/toju-app/src/styles.scss
index 5c117b3..8196869 100644
--- a/toju-app/src/styles.scss
+++ b/toju-app/src/styles.scss
@@ -87,3 +87,306 @@
   --ring: 214 72% 50%;
   --radius: 0.375rem;
 }
+
+.theme-icon-slot {
+  display: none;
+}
+
+.theme-icon-slot[data-theme-visible='true'] {
+  display: inline-flex;
+}
+
+.theme-settings__workspace {
+  display: grid;
+  gap: 1.5rem;
+  grid-template-columns: minmax(18rem, 22rem) minmax(0, 1fr);
+  align-items: start;
+  min-height: 0;
+}
+
+.theme-settings__sidebar {
+  position: sticky;
+  top: 0;
+  display: flex;
+  min-height: 0;
+  flex-direction: column;
+  gap: 1rem;
+}
+
+.theme-settings__main {
+  display: flex;
+  min-width: 0;
+  min-height: 0;
+  flex-direction: column;
+  gap: 1.5rem;
+}
+
+.theme-settings--fullscreen .theme-settings__workspace {
+  gap: 0.875rem;
+  grid-template-columns: minmax(15.5rem, 17rem) minmax(0, 1fr);
+  align-items: stretch;
+}
+
+.theme-studio-fullscreen-shell {
+  overscroll-behavior: contain;
+  scrollbar-gutter: stable both-edges;
+  scrollbar-width: thin;
+  scrollbar-color: hsl(var(--muted-foreground) / 0.6) hsl(var(--card) / 0.75);
+}
+
+.theme-studio-fullscreen-shell::-webkit-scrollbar {
+  width: 10px;
+}
+
+.theme-studio-fullscreen-shell::-webkit-scrollbar-track {
+  border-radius: 999px;
+  background: hsl(var(--card) / 0.75);
+}
+
+.theme-studio-fullscreen-shell::-webkit-scrollbar-thumb {
+  border: 2px solid transparent;
+  border-radius: 999px;
+  background: hsl(var(--muted-foreground) / 0.6);
+  background-clip: padding-box;
+}
+
+.theme-studio-fullscreen-shell::-webkit-scrollbar-thumb:hover {
+  background: hsl(var(--primary) / 0.45);
+  background-clip: padding-box;
+}
+
+.theme-settings--fullscreen .theme-settings__sidebar {
+  gap: 0.75rem;
+}
+
+.theme-settings--fullscreen .theme-settings__sidebar .theme-studio-card:last-child {
+  display: flex;
+  min-height: 0;
+  flex: 1 1 auto;
+  flex-direction: column;
+}
+
+.theme-settings--fullscreen .theme-settings__main {
+  gap: 0.875rem;
+}
+
+.theme-settings--fullscreen .theme-studio-card {
+  border-radius: 1rem;
+  box-shadow: 0 10px 24px rgb(15 23 42 / 0.08);
+}
+
+.theme-settings--fullscreen .theme-settings__hero-grid {
+  gap: 0.55rem;
+}
+
+.theme-settings--fullscreen .theme-settings__hero-stat {
+  border-radius: 0.85rem;
+  padding: 0.7rem 0.85rem;
+}
+
+.theme-settings--fullscreen .theme-settings__hero-label {
+  font-size: 0.64rem;
+}
+
+.theme-settings--fullscreen .theme-settings__hero-value {
+  margin-top: 0.3rem;
+  font-size: 0.92rem;
+}
+
+.theme-settings--fullscreen .theme-settings__workspace-tab,
+.theme-settings--fullscreen .theme-settings__entry-button {
+  border-radius: 0.85rem;
+  padding: 0.72rem 0.8rem;
+}
+
+.theme-settings--fullscreen .theme-settings__search-input {
+  border-radius: 0.85rem;
+  padding: 0.72rem 0.85rem;
+}
+
+.theme-settings--fullscreen .theme-settings__entry-list {
+  max-height: none;
+  min-height: 0;
+  flex: 1 1 auto;
+}
+
+.theme-studio-card {
+  border: 1px solid hsl(var(--border));
+  border-radius: 1.5rem;
+  background:
+    linear-gradient(180deg, hsl(var(--card) / 0.96), hsl(var(--background) / 0.96)),
+    radial-gradient(circle at top right, hsl(var(--primary) / 0.08), transparent 45%);
+  box-shadow: 0 14px 34px rgb(15 23 42 / 0.08);
+}
+
+.theme-settings__hero-grid {
+  display: grid;
+  gap: 0.75rem;
+  grid-template-columns: repeat(4, minmax(0, 1fr));
+}
+
+.theme-settings__hero-stat {
+  border: 1px solid hsl(var(--border));
+  border-radius: 1rem;
+  background: hsl(var(--background) / 0.72);
+  padding: 0.9rem 1rem;
+}
+
+.theme-settings__hero-label {
+  display: block;
+  font-size: 0.7rem;
+  font-weight: 700;
+  letter-spacing: 0.18em;
+  text-transform: uppercase;
+  color: hsl(var(--muted-foreground));
+}
+
+.theme-settings__hero-value {
+  display: block;
+  margin-top: 0.45rem;
+  font-size: 0.98rem;
+  color: hsl(var(--foreground));
+}
+
+.theme-settings__workspace-tab {
+  display: block;
+  width: 100%;
+  border: 1px solid hsl(var(--border));
+  border-radius: 1rem;
+  background: hsl(var(--background) / 0.72);
+  padding: 0.85rem 0.95rem;
+  text-align: left;
+  transition:
+    background-color 160ms ease,
+    border-color 160ms ease,
+    transform 160ms ease,
+    box-shadow 160ms ease;
+}
+
+.theme-settings__workspace-tab:hover {
+  background: hsl(var(--secondary) / 0.78);
+  transform: translateY(-1px);
+}
+
+.theme-settings__workspace-tab--active {
+  border-color: hsl(var(--primary) / 0.4);
+  background: hsl(var(--primary) / 0.08);
+  box-shadow: 0 8px 22px hsl(var(--primary) / 0.12);
+}
+
+.theme-settings__workspace-tab-title {
+  display: block;
+  font-size: 0.92rem;
+  font-weight: 700;
+  color: hsl(var(--foreground));
+}
+
+.theme-settings__workspace-tab-description {
+  display: block;
+  margin-top: 0.35rem;
+  font-size: 0.76rem;
+  line-height: 1.45;
+  color: hsl(var(--muted-foreground));
+}
+
+.theme-settings__search-input {
+  border: 1px solid hsl(var(--border));
+  border-radius: 0.95rem;
+  background: hsl(var(--background) / 0.82);
+  padding: 0.8rem 0.95rem;
+  font-size: 0.9rem;
+  color: hsl(var(--foreground));
+  outline: none;
+  transition:
+    border-color 160ms ease,
+    box-shadow 160ms ease,
+    background-color 160ms ease;
+}
+
+.theme-settings__search-input:focus {
+  border-color: hsl(var(--primary) / 0.4);
+  box-shadow: 0 0 0 3px hsl(var(--primary) / 0.12);
+}
+
+.theme-settings__entry-list {
+  display: flex;
+  max-height: min(60vh, 34rem);
+  flex-direction: column;
+  gap: 0.7rem;
+  overflow: auto;
+  padding-right: 0.15rem;
+}
+
+.theme-settings__entry-button {
+  display: block;
+  width: 100%;
+  border: 1px solid hsl(var(--border));
+  border-radius: 1rem;
+  background: hsl(var(--background) / 0.72);
+  padding: 0.9rem 0.95rem;
+  text-align: left;
+  transition:
+    background-color 160ms ease,
+    border-color 160ms ease,
+    transform 160ms ease,
+    box-shadow 160ms ease;
+}
+
+.theme-settings__entry-button:hover {
+  background: hsl(var(--secondary) / 0.72);
+  transform: translateY(-1px);
+}
+
+.theme-settings__entry-button--active {
+  border-color: hsl(var(--primary) / 0.42);
+  background: hsl(var(--primary) / 0.08);
+  box-shadow: 0 8px 24px hsl(var(--primary) / 0.12);
+}
+
+@media (max-width: 1279px) {
+  .theme-settings__hero-grid {
+    grid-template-columns: repeat(2, minmax(0, 1fr));
+  }
+}
+
+@media (max-width: 1100px) {
+  .theme-settings__workspace {
+    grid-template-columns: minmax(0, 1fr);
+  }
+
+  .theme-settings__sidebar {
+    position: static;
+  }
+
+  .theme-settings__entry-list {
+    max-height: 24rem;
+  }
+}
+
+@media (max-width: 640px) {
+  .theme-settings__hero-grid {
+    grid-template-columns: minmax(0, 1fr);
+  }
+}
+
+[data-theme-key][data-theme-linked='true'] {
+  cursor: pointer;
+}
+
+[data-theme-key][data-theme-picker-active='true'] {
+  cursor: crosshair;
+}
+
+[data-theme-key][data-theme-picker-hovered='true'] {
+  outline: 2px solid hsl(var(--primary));
+  outline-offset: -2px;
+  box-shadow: inset 0 0 0 9999px hsl(var(--primary) / 0.08);
+}
+
+[data-theme-key][data-theme-picker-selected='true'] {
+  outline: 2px solid hsl(var(--primary));
+  outline-offset: -2px;
+  box-shadow:
+    0 0 0 3px hsl(var(--primary) / 0.18),
+    inset 0 0 0 9999px hsl(var(--primary) / 0.06);
+}