Add shifting rainbow gradient animation to rain page title

src/components/SubpageRain.astro

@@ -144,9 +144,23 @@ window.rainData = function() {
 
         <div class="border-b border-stone-800 pb-6">
             <span class="text-xs text-emerald-500 font-mono uppercase tracking-widest block mb-2">Atmosphäre & Ökologie</span>
-            <h1 class="text-4xl sm:text-5xl font-luxury font-bold text-white">Regen für Gemütlichkeit</h1>
+            <h1 class="text-4xl sm:text-5xl font-luxury font-bold rainbow-text">Regen für Gemütlichkeit</h1>
         </div>
         
+        <style>
+        .rainbow-text {
+            background: linear-gradient(to right, #ff2a2a, #ff7e2a, #ffea2a, #2aff2a, #2a7eff, #8a2be2, #ff2a2a);
+            background-size: 200% auto;
+            -webkit-background-clip: text;
+            -webkit-text-fill-color: transparent;
+            animation: rainbow 4s linear infinite;
+        }
+        @keyframes rainbow {
+            0% { background-position: 0% 50%; }
+            100% { background-position: 200% 50%; }
+        }
+        </style>
+
         <!-- Controls (Togglebar) -->
         <div class="glass p-8 rounded-2xl border border-stone-800">
             <div class="flex justify-between items-center cursor-pointer select-none" @click="rainOpen = !rainOpen">