*{box-sizing:border-box;-webkit-tap-highlight-color:transparent}
html,body{margin:0;height:100%;background:#faf8ef;color:#776e65;font-family:system-ui,-apple-system,Segoe UI,Roboto,sans-serif;overscroll-behavior:none;touch-action:none}
main{max-width:480px;margin:0 auto;padding:max(12px,env(safe-area-inset-top)) 14px 14px;display:flex;flex-direction:column;gap:10px}
header{display:flex;justify-content:space-between;align-items:center}h1{margin:0;font-size:3rem;color:#776e65}
.scores{display:flex;gap:8px}.scores div{background:#bbada0;border-radius:6px;padding:6px 14px;text-align:center;color:#fff;min-width:68px}
.scores small{display:block;font-size:.65rem;opacity:.85}.scores b{font-size:1.2rem}
#message{min-height:1.4em;margin:0;text-align:center;font-weight:700;opacity:0}#message.show{opacity:1}
.grid{display:grid;grid-template-columns:repeat(4,1fr);gap:10px;background:#bbada0;border-radius:8px;padding:10px;aspect-ratio:1/1}
.tile{display:flex;align-items:center;justify-content:center;border-radius:5px;font-weight:800;font-size:clamp(1.3rem,8vw,2.4rem);background:rgba(238,228,218,.35)}
.v2{background:#eee4da;color:#776e65}.v4{background:#ede0c8;color:#776e65}.v8{background:#f2b179;color:#f9f6f2}.v16{background:#f59563;color:#f9f6f2}
.v32{background:#f67c5f;color:#f9f6f2}.v64{background:#f65e3b;color:#f9f6f2}.v128{background:#edcf72;color:#f9f6f2;font-size:clamp(1.1rem,7vw,2rem)}
.v256{background:#edcc61;color:#f9f6f2;font-size:clamp(1.1rem,7vw,2rem)}.v512{background:#edc850;color:#f9f6f2;font-size:clamp(1.1rem,7vw,2rem)}
.v1024{background:#edc53f;color:#f9f6f2;font-size:clamp(.95rem,6vw,1.7rem)}.v2048{background:#edc22e;color:#f9f6f2;font-size:clamp(.95rem,6vw,1.7rem)}
.vx{background:#3c3a32;color:#f9f6f2;font-size:clamp(.9rem,5.5vw,1.5rem)}
button{align-self:center;background:#8f7a66;color:#f9f6f2;border:0;border-radius:6px;padding:12px 22px;font-size:1rem;font-weight:700;cursor:pointer}
.hint{text-align:center;margin:0;font-size:.85rem;opacity:.8}