Submit success mit own windows

src/routes/+page.svelte

@@ -25,11 +25,36 @@
   let success = false;
   let dienststellen: any[];
 
+  let fileInputKey = 0;
+  let pdfDatein = [];
+
   onMount(async () => {
     const res = await fetch('/api/dienststellen');
     dienststellen = await res.json();
   });
 
+  function resetForm() {
+    anrede = '';
+    vorname = '';
+    nachname = '';
+    geburtsdatum = '';
+    strasse = '';
+    hausnummer = '';
+    ort = '';
+    plz = '';
+    telefon = '';
+    email = '';
+    schulart = '';
+    zeitraum = '';
+    wunsch1Id = '';
+    wunsch2Id = '';
+    wunsch3Id = '';
+    motivation = '';
+    pdfDateien = [];
+    fileInputKey += 1;
+    success = false;
+  }
+
   async function anmelden() {
     const data = new FormData();
 
@@ -103,21 +128,25 @@
     <div class="grid grid-cols-1 gap-4">
       <select bind:value={wunsch1Id} required>
         <option value="" disabled selected>1. Wunschdienststelle</option>
-        {#each dienststellen as d}
+        {#each (dienststellen ?? []).filter(d => d.plaetze > 0) as d}
           <option value={d.id}>{d.name}</option>
         {/each}
       </select>
 
       <select bind:value={wunsch2Id} required>
         <option value="" disabled selected>2. Wunschdienststelle</option>
-        {#each dienststellen as d}
+        {#each (dienststellen ?? []).filter(d => d.plaetze > 0 && d.id !== wunsch1Id) as d}
           <option value={d.id}>{d.name}</option>
         {/each}
       </select>
 
       <select bind:value={wunsch3Id} required>
         <option value="" disabled selected>3. Wunschdienststelle</option>
-        {#each dienststellen as d}
+        {#each (dienststellen ?? []).filter(d => 
+           d.plaetze > 0 &&
+           d.id !== wunsch1Id &&
+           d.id !== wunsch2Id
+        ) as d}
           <option value={d.id}>{d.name}</option>
         {/each}
     </select>
@@ -129,6 +158,7 @@
     </textarea>
 
     <!-- Mehrere PDF Upload -->
+    {#key fileInputKey}
       <div>
         <label for="pdf-upload" class="block text-gray-700 font-medium mb-1">PDFs hochladen (optional):</label>
         <input
@@ -140,6 +170,7 @@
           class="input"
         />
       </div>
+    {/key}
 
     <!-- Button -->
     <button type="submit"
@@ -148,7 +179,17 @@
     </button>
 
     {#if success}
-      <p class="text-green-600 font-semibold text-center">Anmeldung erfolgreich gesendet!</p>
+      <div class="fixed inset-0 bg-black bg-opacity-50 flex items-center justify-center z-50">
+        <div class="bg-white p-6 rounded shadow-lg text-center space-y-4 max-w-sm w-full">
+          <p class="text-green-600 font-semibold">Anmeldung erfolgreich gesendet!</p>
+          <button
+            class="bg-blue-600 text-white px-4 py-2 rounded hover:bg-blue-700"
+            on:click={resetForm}
+          >
+            OK
+          </button>
+        </div>
+      </div>
     {/if}
 
     {#if fehler}