Code formatting cleanup and addition of visual assets (logo, background)

public/js/present.js

@@ -106,7 +106,7 @@ function PresentApp() {
     if (phase === 'need-config') {
         return (
             <div className="min-h-screen flex flex-col items-center justify-center p-8">
-                <div className="text-6xl mb-4">🚨</div>
+                <img src="/img/logo.png" alt="Quizalarm" className="w-24 h-24 mb-2" />
                 <h1 className="text-3xl font-bold mb-4 fire-gradient">Quizalarm — Präsentation</h1>
                 <p className="text-gray-400 mb-4 text-center">Öffne diesen Link aus dem Admin-Panel.<br />Die URL muss <code className="bg-gray-800 px-2 py-1 rounded">?token=PASSWORT#CODE</code> enthalten.</p>
             </div>
@@ -124,7 +124,7 @@ function PresentApp() {
 
     if (phase === 'waiting') return (
         <div className="min-h-screen flex flex-col items-center justify-center p-8">
-            <div className="text-6xl mb-4">🚨</div>
+            <img src="/img/logo.png" alt="Quizalarm" className="w-24 h-24 mb-2" />
             <h1 className="text-4xl font-extrabold mb-4 fire-gradient">Quizalarm</h1>
             <p className="text-gray-400 text-xl mb-6">{session?.setName}</p>
             <div className="text-8xl font-mono font-extrabold tracking-widest text-red-500 mb-8">{session?.code}</div>