fix view port rendering to include

cmd/client/web/game.js

@@ -856,6 +856,41 @@ function restartGame() {
     console.log('✅ Game restarted - ready to play again');
 }
 
+// ===== FULLSCREEN =====
+
+function toggleFullscreen() {
+    if (!document.fullscreenElement) {
+        document.documentElement.requestFullscreen().catch(() => {});
+    } else {
+        document.exitFullscreen().catch(() => {});
+    }
+}
+
+function updateFullscreenBtn() {
+    const btn = document.getElementById('fullscreen-btn');
+    if (!btn) return;
+    btn.textContent = document.fullscreenElement ? '✕' : '⛶';
+    btn.title = document.fullscreenElement ? 'Vollbild beenden' : 'Vollbild';
+}
+
+document.addEventListener('fullscreenchange', updateFullscreenBtn);
+
+// Auto-Fullscreen beim ersten Nutzer-Klick
+let autoFullscreenDone = false;
+document.addEventListener('click', function requestAutoFullscreen() {
+    if (!autoFullscreenDone && !document.fullscreenElement) {
+        autoFullscreenDone = true;
+        document.documentElement.requestFullscreen().catch(() => {});
+    }
+}, { once: false, capture: true });
+
+document.addEventListener('touchstart', function requestAutoFullscreenTouch() {
+    if (!autoFullscreenDone && !document.fullscreenElement) {
+        autoFullscreenDone = true;
+        document.documentElement.requestFullscreen().catch(() => {});
+    }
+}, { once: false, capture: true });
+
 // Export functions for WASM to call
 window.showMenu = showMenu;
 window.hideMenu = hideMenu;