diff --git a/apps/desktop/src/components/site-header.tsx b/apps/desktop/src/components/site-header.tsx
index 270e33b..8bd6702 100644
--- a/apps/desktop/src/components/site-header.tsx
+++ b/apps/desktop/src/components/site-header.tsx
@@ -17,6 +17,13 @@ export function SiteHeader({ currentView }: SiteHeaderProps) {
   const router = useRouter();
   const [canGoBack, setCanGoBack] = useState(false);
   const [canGoForward, setCanGoForward] = useState(false);
+  const [isMacOS, setIsMacOS] = useState(false);
+
+  useEffect(() => {
+    // Detect if running on macOS
+    const platform = navigator.platform || navigator.userAgent;
+    setIsMacOS(/Mac|Darwin/i.test(platform));
+  }, []);
 
   useEffect(() => {
     // Track navigation history in session storage
@@ -136,7 +143,7 @@ export function SiteHeader({ currentView }: SiteHeaderProps) {
     >
       <div className="flex w-full items-center gap-1">
         {/* macOS traffic light button spacing */}
-        <div className="w-[78px] flex-shrink-0" />
+        {isMacOS && <div className="w-[78px] flex-shrink-0" />}
 
         <div className="flex items-center gap-1 px-4 lg:gap-2 lg:px-6 py-1.5">
           <SidebarTrigger className="-ml-1" style={noDragRegion} />
diff --git a/apps/desktop/src/components/theme-toggle.tsx b/apps/desktop/src/components/theme-toggle.tsx
index f6bd499..6b06a5f 100644
--- a/apps/desktop/src/components/theme-toggle.tsx
+++ b/apps/desktop/src/components/theme-toggle.tsx
@@ -1,6 +1,7 @@
 import * as React from "react";
 import { Moon, Sun, Monitor } from "lucide-react";
 import { useTheme } from "next-themes";
+import { api } from "@/trpc/react";
 
 import { Button } from "@/components/ui/button";
 import {
@@ -11,7 +12,16 @@ import {
 } from "@/components/ui/dropdown-menu";
 
 export function ThemeToggle() {
-  const { setTheme, theme } = useTheme();
+  const { setTheme } = useTheme();
+  const updateUIThemeMutation = api.settings.updateUITheme.useMutation();
+
+  const handleThemeChange = (newTheme: "light" | "dark" | "system") => {
+    // Update local theme immediately for instant feedback
+    setTheme(newTheme);
+
+    // Sync with backend
+    updateUIThemeMutation.mutate({ theme: newTheme });
+  };
 
   return (
     <DropdownMenu>
@@ -23,15 +33,15 @@ export function ThemeToggle() {
         </Button>
       </DropdownMenuTrigger>
       <DropdownMenuContent align="end">
-        <DropdownMenuItem onClick={() => setTheme("light")}>
+        <DropdownMenuItem onClick={() => handleThemeChange("light")}>
           <Sun className="mr-2 h-4 w-4" />
           <span>Light</span>
         </DropdownMenuItem>
-        <DropdownMenuItem onClick={() => setTheme("dark")}>
+        <DropdownMenuItem onClick={() => handleThemeChange("dark")}>
           <Moon className="mr-2 h-4 w-4" />
           <span>Dark</span>
         </DropdownMenuItem>
-        <DropdownMenuItem onClick={() => setTheme("system")}>
+        <DropdownMenuItem onClick={() => handleThemeChange("system")}>
           <Monitor className="mr-2 h-4 w-4" />
           <span>System</span>
         </DropdownMenuItem>
@@ -39,25 +49,3 @@ export function ThemeToggle() {
     </DropdownMenu>
   );
 }
-
-export function ThemeToggleSimple() {
-  const { setTheme, theme } = useTheme();
-
-  const toggleTheme = () => {
-    if (theme === "light") {
-      setTheme("dark");
-    } else if (theme === "dark") {
-      setTheme("system");
-    } else {
-      setTheme("light");
-    }
-  };
-
-  return (
-    <Button variant="outline" size="icon" onClick={toggleTheme}>
-      <Sun className="h-[1.2rem] w-[1.2rem] rotate-0 scale-100 transition-all dark:-rotate-90 dark:scale-0" />
-      <Moon className="absolute h-[1.2rem] w-[1.2rem] rotate-90 scale-0 transition-all dark:rotate-0 dark:scale-100" />
-      <span className="sr-only">Toggle theme</span>
-    </Button>
-  );
-}
diff --git a/apps/desktop/src/db/app-settings.ts b/apps/desktop/src/db/app-settings.ts
index 70cc9ee..0441ffc 100644
--- a/apps/desktop/src/db/app-settings.ts
+++ b/apps/desktop/src/db/app-settings.ts
@@ -48,8 +48,6 @@ const defaultSettings: AppSettingsData = {
   },
   ui: {
     theme: "system",
-    sidebarOpen: false,
-    currentView: "Voice Recording",
   },
   transcription: {
     language: "en",
diff --git a/apps/desktop/src/db/schema.ts b/apps/desktop/src/db/schema.ts
index f9fa3f4..9511cc3 100644
--- a/apps/desktop/src/db/schema.ts
+++ b/apps/desktop/src/db/schema.ts
@@ -115,14 +115,6 @@ export interface AppSettingsData {
   };
   ui?: {
     theme: "light" | "dark" | "system";
-    sidebarOpen?: boolean;
-    currentView?: string;
-    windowBounds?: {
-      x: number;
-      y: number;
-      width: number;
-      height: number;
-    };
   };
   transcription?: {
     language: string;
diff --git a/apps/desktop/src/main/core/window-manager.ts b/apps/desktop/src/main/core/window-manager.ts
index 2a3a0a2..fabe3f9 100644
--- a/apps/desktop/src/main/core/window-manager.ts
+++ b/apps/desktop/src/main/core/window-manager.ts
@@ -1,4 +1,10 @@
-import { BrowserWindow, screen, systemPreferences, app } from "electron";
+import {
+  BrowserWindow,
+  screen,
+  systemPreferences,
+  app,
+  nativeTheme,
+} from "electron";
 import path from "node:path";
 import { logger } from "../logger";
 import { ServiceManager } from "../managers/service-manager";
@@ -16,22 +22,105 @@ export class WindowManager {
   private onboardingWindow: BrowserWindow | null = null;
   private widgetDisplayId: number | null = null;
   private cursorPollingInterval: NodeJS.Timeout | null = null;
+  private themeListenerSetup: boolean = false;
 
-  createOrShowMainWindow(): void {
+  private async getThemeColors(): Promise<{
+    backgroundColor: string;
+    symbolColor: string;
+  }> {
+    try {
+      const settingsService =
+        ServiceManager.getInstance()?.getService("settingsService");
+      if (!settingsService) {
+        // Default to light theme if service unavailable
+        return { backgroundColor: "#ffffff", symbolColor: "#000000" };
+      }
+
+      const uiSettings = await settingsService.getUISettings();
+      const theme = uiSettings?.theme || "system";
+
+      // Determine if we should use dark colors
+      let isDark = false;
+      if (theme === "dark") {
+        isDark = true;
+      } else if (theme === "light") {
+        isDark = false;
+      } else if (theme === "system") {
+        isDark = nativeTheme.shouldUseDarkColors;
+      }
+
+      // Return appropriate colors
+      return isDark
+        ? { backgroundColor: "#171717", symbolColor: "#fafafa" }
+        : { backgroundColor: "#ffffff", symbolColor: "#171717" };
+    } catch (error) {
+      logger.main.error("Failed to get theme colors:", error);
+      // Default to light theme on error
+      return { backgroundColor: "#ffffff", symbolColor: "#000000" };
+    }
+  }
+
+  async updateAllWindowThemes(): Promise<void> {
+    const colors = await this.getThemeColors();
+
+    // Update main window
+    if (this.mainWindow && !this.mainWindow.isDestroyed()) {
+      this.mainWindow.setTitleBarOverlay({
+        color: colors.backgroundColor,
+        symbolColor: colors.symbolColor,
+        height: 32,
+      });
+    }
+
+    // Update onboarding window if it exists
+    // Note: onboarding window has frame: false, so no title bar to update
+
+    logger.main.info("Updated window themes", colors);
+  }
+
+  private setupThemeListener(): void {
+    if (this.themeListenerSetup) return;
+
+    // Listen for system theme changes
+    nativeTheme.on("updated", async () => {
+      const settingsService =
+        ServiceManager.getInstance()!.getService("settingsService")!;
+
+      const uiSettings = await settingsService.getUISettings();
+      const theme = uiSettings?.theme || "system";
+
+      // Only update if theme is set to "system"
+      if (theme === "system") {
+        await this.updateAllWindowThemes();
+        logger.main.info("System theme changed, updating windows");
+      }
+    });
+
+    this.themeListenerSetup = true;
+    logger.main.info("Theme listener setup complete");
+  }
+
+  async createOrShowMainWindow(): Promise<void> {
     if (this.mainWindow && !this.mainWindow.isDestroyed()) {
       this.mainWindow.show();
       this.mainWindow.focus();
       return;
     }
 
+    // Setup theme listener on first window creation
+    this.setupThemeListener();
+
+    // Get theme colors before creating window
+    const colors = await this.getThemeColors();
+
     this.mainWindow = new BrowserWindow({
       width: 1200,
       height: 800,
       frame: true,
       titleBarStyle: "hidden",
       titleBarOverlay: {
-        color: "#ffffff",
-        symbolColor: "#000000",
+        color: colors.backgroundColor,
+        symbolColor: colors.symbolColor,
         height: 32,
       },
       trafficLightPosition: { x: 20, y: 16 },
@@ -170,6 +259,9 @@ export class WindowManager {
       return;
     }
 
+    // Setup theme listener if not already done
+    this.setupThemeListener();
+
     this.onboardingWindow = new BrowserWindow({
       width: 700,
       height: 600,
diff --git a/apps/desktop/src/pipeline/providers/transcription/simple-fork-wrapper.ts b/apps/desktop/src/pipeline/providers/transcription/simple-fork-wrapper.ts
index 236e1dc..750502d 100644
--- a/apps/desktop/src/pipeline/providers/transcription/simple-fork-wrapper.ts
+++ b/apps/desktop/src/pipeline/providers/transcription/simple-fork-wrapper.ts
@@ -61,7 +61,7 @@ export class SimpleForkWrapper {
     this.worker = fork(actualWorkerPath, [], {
       execPath: this.nodeBinaryPath,
       env: workerEnv,
-      silent: false,
+      silent: true,
       cwd: app.isPackaged ? process.resourcesPath : process.cwd(),
     });
 
diff --git a/apps/desktop/src/services/settings-service.ts b/apps/desktop/src/services/settings-service.ts
index 4525267..7a6e359 100644
--- a/apps/desktop/src/services/settings-service.ts
+++ b/apps/desktop/src/services/settings-service.ts
@@ -7,7 +7,7 @@ import {
   updateAppSettings,
 } from "../db/app-settings";
 import type { AppSettingsData } from "../db/schema";
-import { isWindows, isMacOS } from "../utils/platform";
+import { isMacOS } from "../utils/platform";
 
 /**
  * Database-backed settings service with typed configuration
@@ -61,7 +61,11 @@ export class SettingsService {
    * Get UI settings
    */
   async getUISettings(): Promise<AppSettingsData["ui"]> {
-    return await getSettingsSection("ui");
+    return (
+      (await getSettingsSection("ui")) ?? {
+        theme: "system",
+      }
+    );
   }
 
   /**
diff --git a/apps/desktop/src/trpc/routers/settings.ts b/apps/desktop/src/trpc/routers/settings.ts
index 8aaf500..e371d2e 100644
--- a/apps/desktop/src/trpc/routers/settings.ts
+++ b/apps/desktop/src/trpc/routers/settings.ts
@@ -42,6 +42,10 @@ const AppPreferencesSchema = z.object({
   showWidgetWhileInactive: z.boolean().optional(),
 });
 
+const UIThemeSchema = z.object({
+  theme: z.enum(["light", "dark", "system"]),
+});
+
 export const settingsRouter = createRouter({
   // Get all settings
   getSettings: procedure.query(async ({ ctx }) => {
@@ -549,6 +553,38 @@ export const settingsRouter = createRouter({
       return true;
     }),
 
+  // Update UI theme
+  updateUITheme: procedure
+    .input(UIThemeSchema)
+    .mutation(async ({ input, ctx }) => {
+      const settingsService = ctx.serviceManager.getService("settingsService");
+      if (!settingsService) {
+        throw new Error("SettingsService not available");
+      }
+
+      // Get current UI settings
+      const currentUISettings = await settingsService.getUISettings();
+
+      // Update with new theme
+      await settingsService.setUISettings({
+        ...currentUISettings,
+        theme: input.theme,
+      });
+
+      // Update all window themes immediately
+      const windowManager = ctx.serviceManager.getService("windowManager");
+      if (windowManager) {
+        await windowManager.updateAllWindowThemes();
+      }
+
+      const logger = ctx.serviceManager.getLogger();
+      if (logger) {
+        logger.main.info("UI theme updated", { theme: input.theme });
+      }
+
+      return true;
+    }),
+
   // Reset app - deletes all data and restarts
   resetApp: procedure.mutation(async ({ ctx }) => {
     try {