body{font-family:'Arial',sans-serif;margin:0;padding:20px;background:linear-gradient(135deg,#667eea 0%,#764ba2 100%);min-height:100vh;color:#333;-webkit-user-select:none;-moz-user-select:none;-ms-user-select:none;user-select:none;-webkit-touch-callout:none;-webkit-tap-highlight-color:transparent}.container{max-width:600px;margin:0 auto;background:rgba(255,255,255,0.95);border-radius:15px;padding:20px;box-shadow:0 10px 30px rgba(0,0,0,0.3)}h1{text-align:center;color:#2c3e50;margin-bottom:20px;font-size:2.5em;text-shadow:2px 2px 4px rgba(0,0,0,0.1)}.info-panel{background:#f8f9fa;border:2px solid #e9ecef;border-radius:8px;padding:15px;margin-bottom:20px}.info-panel p{margin:5px 0;font-size:14px}.controls{display:flex;justify-content:space-between;align-items:center;margin-bottom:20px;flex-wrap:wrap;gap:10px}button{background:linear-gradient(45deg,#3498db,#2980b9);color:white;border:0;padding:10px 20px;border-radius:5px;cursor:pointer;font-size:14px;transition:all .3s ease;box-shadow:0 4px 8px rgba(0,0,0,0.2)}button:hover{transform:translateY(-2px);box-shadow:0 6px 12px rgba(0,0,0,0.3)}button:active{transform:translateY(0)}button:disabled{background:#95a5a6;cursor:not-allowed;opacity:.6}button:disabled:hover{transform:none;box-shadow:0 4px 8px rgba(0,0,0,0.2)}#moveCounter,#timer{background:#34495e;color:white;padding:8px 15px;border-radius:20px;font-weight:bold;font-size:14px}#gameBoard{display:grid;grid-template-columns:repeat(4,100px);grid-template-rows:repeat(4,100px);gap:5px;justify-content:center;background:#2c3e50;padding:10px;border-radius:10px;margin:20px auto;box-shadow:inset 0 4px 8px rgba(0,0,0,0.3);width:fit-content}.tile{width:var(--tile-size,100px);height:var(--tile-size,100px);background:linear-gradient(135deg,#3498db,#2980b9);border:2px solid #2471a3;border-radius:8px;display:flex;align-items:center;justify-content:center;font-size:2em;font-weight:bold;color:white;cursor:pointer;transition:all .3s ease;box-shadow:0 4px 8px rgba(0,0,0,0.3);text-shadow:2px 2px 4px rgba(0,0,0,0.3)}.tile:hover{transform:scale(1.05);box-shadow:0 6px 12px rgba(0,0,0,0.4)}.tile.movable{cursor:pointer;animation:pulse 2s infinite}.tile.empty{background:#34495e;border:2px dashed #5d6d7e;cursor:default;box-shadow:inset 0 2px 4px rgba(0,0,0,0.3)}.tile.empty:hover{transform:none;box-shadow:inset 0 2px 4px rgba(0,0,0,0.3)}.tile.moving{animation:move .3s ease-in-out}@keyframes pulse{0%,100%{opacity:1}50%{opacity:.9}}@keyframes move{0%{transform:scale(1)}50%{transform:scale(1.1)}100%{transform:scale(1)}}.instructions{background:#f8f9fa;border-radius:8px;padding:20px;margin-top:20px;border-left:4px solid #3498db}.instructions h3{margin-top:0;color:#2c3e50}.instructions ul{padding-left:20px}.instructions li{margin:8px 0;line-height:1.4}@media(max-width:768px){body{padding:10px}.container{margin:5px;padding:10px;max-width:100%}h1{font-size:1.8em;margin-bottom:15px}.info-panel{padding:10px;margin-bottom:15px;font-size:13px}.controls{justify-content:center;text-align:center;gap:8px;margin-bottom:15px}button{padding:8px 12px;font-size:12px;margin:2px}#moveCounter,#timer{padding:6px 10px;font-size:12px}#gameBoard{gap:3px;padding:8px;margin:10px auto}.instructions{padding:15px;font-size:13px}.instructions li{margin:6px 0;line-height:1.3}}@media(max-width:480px){body{padding:5px}.container{margin:0;padding:5px;max-width:100%}h1{font-size:1.5em;margin-bottom:8px;margin-top:5px}.info-panel{padding:6px;margin-bottom:8px;font-size:11px;display:none}.controls{flex-direction:column;gap:4px;margin-bottom:8px}button{width:100%;padding:8px 6px;font-size:11px}#moveCounter,#timer{padding:4px 8px;font-size:11px}#gameBoard{gap:2px;padding:4px;margin:5px auto}.instructions{padding:8px;font-size:11px;display:none}}