*{box-sizing:border-box;margin:0;padding:0}html,body{width:100%;height:100%;overflow:hidden;background:#0a0a12;font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Oxygen,Ubuntu,sans-serif;color:#e4e4e7}.cascade-root{position:fixed;inset:0}#cascade-canvas{display:block;width:100%;height:100%}.game-container{position:fixed;top:50%;left:50%;transform:translate(-50%,-50%);width:380px;display:flex;flex-direction:column;gap:10px;z-index:10;user-select:none;-webkit-user-select:none}.header{display:flex;justify-content:space-between;align-items:center}.title-area{display:flex;align-items:center;gap:10px}.back{color:#ffffff80;text-decoration:none;font-size:1.2rem;transition:color .2s}.back:hover{color:#fff}h1{font-size:1.6rem;font-weight:700;color:#fff;text-shadow:0 2px 12px rgba(0,0,0,.5)}.scores{display:flex;gap:6px}.score-box{display:flex;flex-direction:column;align-items:center;padding:6px 14px;border-radius:8px;background:#ffffff14;backdrop-filter:blur(12px);-webkit-backdrop-filter:blur(12px);min-width:70px}.score-label{font-size:.6rem;letter-spacing:.1em;color:#ffffff73;font-weight:600}.score-value{font-size:1.1rem;font-weight:700;color:#fff;font-variant-numeric:tabular-nums}.sub-header{display:flex;justify-content:space-between;align-items:center}.tagline{font-size:.8rem;color:#fff6}.new-game-btn{padding:6px 14px;border:none;border-radius:6px;background:#818cf84d;color:#c7d2fe;font-size:.78rem;font-weight:600;cursor:pointer;transition:background .2s}.new-game-btn:hover{background:#818cf880}.grid-wrapper{position:relative}.grid{display:grid;grid-template-columns:repeat(4,1fr);gap:8px;padding:8px;border-radius:12px;background:#0f0f1980;backdrop-filter:blur(20px) saturate(1.4);-webkit-backdrop-filter:blur(20px) saturate(1.4);border:1px solid rgba(255,255,255,.06);position:relative}.cell{aspect-ratio:1;border-radius:8px;background:#ffffff0a}.tile{position:absolute;--gap: 8px;--pad: 8px;--cell-size: calc((100% - var(--pad) * 2 - var(--gap) * 3) / 4);width:var(--cell-size);height:var(--cell-size);left:calc(var(--pad) + var(--col) * (var(--cell-size) + var(--gap)));top:calc(var(--pad) + var(--row) * (var(--cell-size) + var(--gap)));border-radius:8px;display:flex;align-items:center;justify-content:center;font-size:1.8rem;font-weight:700;color:#1a1a2e;text-shadow:0 1px 2px rgba(0,0,0,.1);z-index:2}.tile.sliding{transition:left .12s ease,top .12s ease}.tile.small-text{font-size:1.3rem}.tile.tile-new{animation:tile-spawn .18s ease-out}@keyframes tile-spawn{0%{transform:scale(0);opacity:0}60%{transform:scale(1.08)}to{transform:scale(1);opacity:1}}.tile.tile-merge{animation:tile-merge-pop .2s ease-out}@keyframes tile-merge-pop{0%{transform:scale(1)}40%{transform:scale(1.25)}to{transform:scale(1)}}.bg-2{background:#77c4d3d9;color:#0f2b33}.bg-4{background:#7bc67ed9;color:#0f2b14}.bg-8{background:#f2b179e6;color:#3d2008}.bg-16{background:#f69563e6;color:#3d1a05}.bg-32{background:#f67c5feb;color:#fff;text-shadow:0 1px 4px rgba(0,0,0,.2)}.bg-64{background:#f65e3beb;color:#fff;text-shadow:0 1px 4px rgba(0,0,0,.2)}.bg-128{background:#edcf72eb;color:#3d2e08;box-shadow:0 0 20px #edcf724d}.bg-256{background:#edcc61eb;color:#3d2e08;box-shadow:0 0 24px #edcc6159}.bg-512{background:#edc850f0;color:#3d2e08;box-shadow:0 0 30px #edc85066}.bg-1024{background:#edc53ff0;color:#fff;box-shadow:0 0 36px #edc53f73;text-shadow:0 1px 4px rgba(0,0,0,.2)}.bg-2048{background:#edc22ef5;color:#fff;box-shadow:0 0 50px #edc22e99,0 0 80px #edc22e4d;text-shadow:0 1px 6px rgba(0,0,0,.3)}.bg-super{background:#3c3a50f2;color:#fff;box-shadow:0 0 40px #818cf866}.message{position:absolute;inset:0;display:flex;align-items:center;justify-content:center;font-size:2rem;font-weight:800;color:#fff;background:#0a0a1299;backdrop-filter:blur(8px);-webkit-backdrop-filter:blur(8px);border-radius:12px;opacity:0;pointer-events:none;transition:opacity .4s;text-shadow:0 2px 16px rgba(0,0,0,.5);z-index:20}.message.show{opacity:1;pointer-events:auto}.hint{text-align:center;font-size:.72rem;color:#ffffff40}.credits{text-align:center;font-size:.68rem;color:#ffffff26}.credits a{color:#ffffff40;text-decoration:none}.credits a:hover{color:#818cf8}@media(max-width:420px){.game-container{width:calc(100vw - 24px)}h1{font-size:1.3rem}.tile{font-size:1.4rem}.tile.small-text{font-size:1rem}}