Red Mode: Nacht-Navigator-Logo mit 'RED RALF MODE'-Bogen

- Logo generiert: unterer Textbogen ersetzt, Goldringe rekonstruiert
- Logo in Karten-Seite + Spielraum-Lobby eingebunden
- Favicon-Swap bei aktivem Red Mode
- ?tab= URL-Param fuer Tab-Auswahl (Screenshots/Deep-Links)

app/src/pages/Cards.tsx

@@ -50,7 +50,11 @@ export default function Cards() {
   const [filter, setFilter] = useState<Filter>('alle')
   const [gezogen, setGezogen] = useState<Spielkarte | null>(null)
   const [zaehler, setZaehler] = useState(0) // triggert Re-Flip-Animation
-  const [redMode, setRedMode] = useState(() => localStorage.getItem(REDMODE_KEY) === '1')
+  const [redMode, setRedMode] = useState(
+    () =>
+      localStorage.getItem(REDMODE_KEY) === '1' ||
+      new URLSearchParams(window.location.search).get('redmode') === '1'
+  )
   useRedMode(redMode)
 
   const toggleRedMode = () => {
@@ -79,6 +83,13 @@ export default function Cards() {
 
   return (
     <div className="px-5 pt-8">
+      {redMode && (
+        <img
+          src="/redmode-logo.png"
+          alt="Red Ralf Mode Logo"
+          className="mx-auto mb-4 w-32 rounded-full shadow-[0_0_36px_rgba(239,68,68,0.4)] ring-2 ring-red-500/40"
+        />
+      )}
       <p className="mb-1 text-xs font-extrabold uppercase tracking-[0.25em] text-violet-300">
         20 Statements · 5 Kategorien
       </p>