Commit 6: Adminbereich (TanStack Router, 8 Menüpunkte, Scan-Logs)

apps/frontend/src/hooks/useTheme.ts

@@ -0,0 +1,22 @@
+import { useEffect, useState } from "react";
+
+export type Theme = "light" | "dark";
+
+export function useTheme(): [Theme, () => void] {
+  const [theme, setTheme] = useState<Theme>(() => {
+    if (typeof window === "undefined") return "dark";
+    const stored = window.localStorage.getItem("launchpad-theme");
+    if (stored === "light" || stored === "dark") return stored;
+    return window.matchMedia("(prefers-color-scheme: dark)").matches
+      ? "dark"
+      : "light";
+  });
+
+  useEffect(() => {
+    document.documentElement.classList.toggle("dark", theme === "dark");
+    window.localStorage.setItem("launchpad-theme", theme);
+  }, [theme]);
+
+  const toggle = () => setTheme((t) => (t === "dark" ? "light" : "dark"));
+  return [theme, toggle];
+}