*{box-sizing:border-box;margin:0;padding:0}body{font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,sans-serif;background:linear-gradient(135deg,#667eea,#764ba2);color:#fff;margin:0;padding:20px;min-height:100vh}.game-container{max-width:500px;margin:0 auto;text-align:center;background:#ffffff1a;-webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);border-radius:20px;padding:30px;box-shadow:0 8px 32px #0000004d;border:1px solid rgba(255,255,255,.18)}.header{margin-bottom:20px}.header h1{font-size:48px;font-weight:700;color:#fff;margin-bottom:10px;text-shadow:0 0 20px rgba(255,255,255,.5);background:linear-gradient(45deg,#fff,#f0f0f0);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}.score-container{display:flex;justify-content:space-between;align-items:center;margin-bottom:20px}.score-box{background:linear-gradient(45deg,#667eea,#764ba2);color:#fff;padding:12px 20px;border-radius:25px;font-size:18px;font-weight:700;box-shadow:0 4px 15px #667eea66;border:2px solid rgba(255,255,255,.2)}.restart-button{background:linear-gradient(45deg,#ff6b6b,#ee5a52);color:#fff;border:none;padding:12px 24px;border-radius:25px;font-size:16px;cursor:pointer;transition:all .3s ease;box-shadow:0 4px 15px #ff6b6b66;border:2px solid rgba(255,255,255,.2);font-weight:600}.restart-button:hover{transform:translateY(-2px);box-shadow:0 6px 20px #ff6b6b99;background:linear-gradient(45deg,#ff5252,#e53e3e)}.game-message{position:fixed;top:50%;left:50%;transform:translate(-50%,-50%);background-color:#fffffff2;padding:40px;border-radius:8px;box-shadow:0 0 20px #0000004d;z-index:1000;text-align:center}.game-message.win{background-color:#edc22ef2;color:#fff}.game-message.game-over{background-color:#eee4daf2;color:#776e65}.game-message h2{margin-bottom:20px;font-size:24px}.game-message button{background-color:#8f7a66;color:#fff;border:none;padding:12px 24px;border-radius:4px;font-size:16px;cursor:pointer;transition:background-color .3s}.game-message button:hover{background-color:#9f8a76}.grid-container{background:#ffffff1a;-webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);border-radius:20px;padding:20px;margin-bottom:20px;display:inline-block;box-shadow:0 8px 32px #0000004d;border:1px solid rgba(255,255,255,.18)}.grid-row{display:flex;gap:8px;margin-bottom:8px}.grid-row:last-child{margin-bottom:0}.grid-cell{width:80px;height:80px;background:#ffffff1a;border-radius:12px;display:flex;align-items:center;justify-content:center;font-size:24px;font-weight:700;transition:all .3s ease;-webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);border:1px solid rgba(255,255,255,.1);box-shadow:0 4px 15px #0000001a}.cell-empty{background:#ffffff0d;color:transparent}.cell-2{background:linear-gradient(45deg,#eee4da,#f2e8de);color:#776e65;animation:cellAppear .3s ease}.cell-4{background:linear-gradient(45deg,#ede0c8,#f1e5cc);color:#776e65;animation:cellAppear .3s ease}.cell-8{background:linear-gradient(45deg,#f2b179,#f5b97a);color:#f9f6f2;animation:cellAppear .3s ease;box-shadow:0 0 20px #f2b17980}.cell-16{background:linear-gradient(45deg,#f59563,#f79d66);color:#f9f6f2;animation:cellAppear .3s ease;box-shadow:0 0 20px #f5956380}.cell-32{background:linear-gradient(45deg,#f67c5f,#f88462);color:#f9f6f2;animation:cellAppear .3s ease;box-shadow:0 0 25px #f67c5f99}.cell-64{background:linear-gradient(45deg,#f65e3b,#f8663e);color:#f9f6f2;animation:cellAppear .3s ease;box-shadow:0 0 25px #f65e3b99}.cell-128{background:linear-gradient(45deg,#edcf72,#f0d275);color:#f9f6f2;font-size:20px;animation:cellAppear .3s ease;box-shadow:0 0 30px #edcf72b3}.cell-256{background:linear-gradient(45deg,#edcc61,#f0cf64);color:#f9f6f2;font-size:20px;animation:cellAppear .3s ease;box-shadow:0 0 30px #edcc61b3}.cell-512{background:linear-gradient(45deg,#edc850,#f0cb53);color:#f9f6f2;font-size:20px;animation:cellAppear .3s ease;box-shadow:0 0 35px #edc850cc}.cell-1024{background:linear-gradient(45deg,#edc53f,#f0c842);color:#f9f6f2;font-size:18px;animation:cellAppear .3s ease;box-shadow:0 0 35px #edc53fcc}.cell-2048{background:linear-gradient(45deg,#edc22e,#f0c531);color:#f9f6f2;font-size:18px;animation:cellAppear .3s ease,glow 2s ease-in-out infinite alternate;box-shadow:0 0 40px #edc22ee6}.cell-4096{background-color:#3c3a32;color:#f9f6f2;font-size:18px}.cell-8192{background-color:#3c3a32;color:#f9f6f2;font-size:16px}.game-explanation{color:#776e65;font-size:14px;line-height:1.4}.game-explanation p{margin-bottom:8px}@keyframes cellAppear{0%{opacity:0;transform:scale(.8)}to{opacity:1;transform:scale(1)}}@keyframes glow{0%{box-shadow:0 0 40px #edc22ee6}to{box-shadow:0 0 60px #edc22e,0 0 80px #edc22eb3}}@keyframes pulse{0%{transform:scale(1)}50%{transform:scale(1.05)}to{transform:scale(1)}}.grid-cell:hover{transform:scale(1.05);box-shadow:0 6px 20px #0003}.game-message{position:fixed;top:50%;left:50%;transform:translate(-50%,-50%);background:#ffffff1a;-webkit-backdrop-filter:blur(20px);backdrop-filter:blur(20px);padding:40px;border-radius:20px;box-shadow:0 8px 32px #0000004d;z-index:1000;text-align:center;border:1px solid rgba(255,255,255,.18);animation:messageAppear .3s ease}@keyframes messageAppear{0%{opacity:0;transform:translate(-50%,-50%) scale(.8)}to{opacity:1;transform:translate(-50%,-50%) scale(1)}}.game-message.win{background:linear-gradient(45deg,#edc22ee6,#ffd700e6);color:#fff}.game-message.game-over{background:linear-gradient(45deg,#eee4dae6,#ffffffe6);color:#776e65}.game-message h2{margin-bottom:20px;font-size:24px;text-shadow:0 2px 4px rgba(0,0,0,.3)}.game-message button{background:linear-gradient(45deg,#667eea,#764ba2);color:#fff;border:none;padding:15px 30px;border-radius:25px;font-size:16px;cursor:pointer;transition:all .3s ease;box-shadow:0 4px 15px #667eea66;border:2px solid rgba(255,255,255,.2);font-weight:600}.game-message button:hover{transform:translateY(-2px);box-shadow:0 6px 20px #667eea99}.game-explanation{color:#ffffffe6;font-size:14px;line-height:1.6;background:#ffffff1a;-webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);padding:20px;border-radius:15px;margin-top:20px;border:1px solid rgba(255,255,255,.18)}@media (max-width: 600px){.game-container{padding:15px;margin:10px;border-radius:15px}.header h1{font-size:36px}.grid-container{padding:15px;border-radius:15px}.grid-cell{width:60px;height:60px;font-size:18px;border-radius:8px}.cell-128,.cell-256,.cell-512{font-size:16px}.cell-1024,.cell-2048,.cell-4096{font-size:14px}.cell-8192{font-size:12px}.game-message{padding:30px;margin:20px;width:calc(100% - 40px);max-width:350px;border-radius:15px}.game-explanation{padding:15px;font-size:13px;border-radius:10px}.score-container{flex-direction:column;gap:15px}.score-box,.restart-button{width:100%;text-align:center}}