diff --git a/src/main/index.ts b/src/main/index.ts
index ef1892f..f73a543 100644
--- a/src/main/index.ts
+++ b/src/main/index.ts
@@ -6,7 +6,7 @@
 
 import "./ipc";
 
-import { app, BrowserWindow } from "electron";
+import { app, BrowserWindow, nativeTheme } from "electron";
 import { checkUpdates } from "updater/main";
 
 import { DATA_DIR } from "./constants";
@@ -15,6 +15,7 @@ import { createWindows, mainWin } from "./mainWindow";
 import { registerMediaPermissionsHandler } from "./mediaPermissions";
 import { registerScreenShareHandler } from "./screenShare";
 import { Settings } from "./settings";
+import { isDeckGameMode } from "./utils/steamOS";
 
 if (IS_DEV) {
     require("source-map-support").install();
@@ -43,6 +44,9 @@ function init() {
         "WinRetrieveSuggestionsOnlyOnDemand,HardwareMediaKeyHandling,MediaSessionService,WidgetLayering"
     );
 
+    // In the Flatpak on SteamOS the theme is detected as light, but SteamOS only has a dark mode, so we just override it
+    if (isDeckGameMode) nativeTheme.themeSource = "dark";
+
     app.on("second-instance", (_event, _cmdLine, _cwd, data: any) => {
         if (data.IS_DEV) app.quit();
         else if (mainWin) {