:root{color-scheme:light;--paper:#f5f3eb;--ink:#283f36;--green:#47735a;--line:#dedfd3;--soft:#e9ebdf;--accent:#d8eca7}*{box-sizing:border-box}body{margin:0;background:var(--paper);color:var(--ink);font-family:-apple-system,BlinkMacSystemFont,"PingFang SC","Microsoft YaHei",sans-serif}header,footer{max-width:1240px;margin:auto;display:flex;justify-content:space-between;align-items:center}header{height:104px;border-bottom:1px solid var(--line)}a{color:inherit;text-decoration:none}.brand{display:flex;align-items:center;gap:12px;letter-spacing:2px;font-size:13px;font-weight:750}.brand-icon{display:grid;place-items:center;width:34px;height:34px;border-radius:10px;background:var(--ink);color:var(--accent);font-size:29px}.header-note{font-size:12px;color:#6a776c;letter-spacing:3px}main{max-width:1112px;margin:66px auto 60px;display:grid;grid-template-columns:1fr 470px;gap:100px}.eyebrow{font-size:11px;font-weight:650;letter-spacing:2px;display:flex;gap:10px;align-items:center}.eyebrow span{width:7px;height:7px;border-radius:50%;background:#77904b}h1{font-size:66px;line-height:1.23;font-weight:650;letter-spacing:-3px;margin:31px 0 24px}.green{color:var(--green)}.lede{color:#768074;font-size:14px;line-height:2.1}.game-name{display:flex;gap:14px;align-items:center;margin:38px 0 30px}.leaf{font-size:39px;color:var(--green)}.game-name strong{font-size:15px;font-weight:600}.game-name small{display:block;font-size:9px;letter-spacing:1.5px;margin-top:7px;color:#84907d}.pill{font-size:10px;border:1px solid #d8dfcc;padding:7px 11px;border-radius:20px;margin-left:13px;color:#6f7c69}.how{border-top:1px solid var(--line);max-width:370px;padding-top:20px}.how h2{font-size:13px;margin:0 0 12px}.how p{font-size:12px;color:#798273;line-height:2.2;max-width:340px}kbd{border:1px solid #d5d9cc;background:#fafbf5;border-radius:4px;padding:0 4px;font-size:12px}.example{display:flex;gap:12px;align-items:center;margin:17px 0}.example span{width:33px;height:33px;display:grid;place-items:center;background:#e8e8d9;border-radius:7px;font-weight:600;font-size:14px}.example b{font-size:12px;font-weight:400;color:#8f988b}.example .merged{background:#d9e1b9}.quiet{font-size:10px;color:#92998b;margin-top:25px}.game-top{display:flex;justify-content:space-between;align-items:center;gap:15px;margin:3px 0 19px}.title-small{font-size:13px;font-weight:550}.title-small span{margin-left:5px;color:#829373}.scores{display:flex;gap:23px}.scores div{min-width:57px;text-align:right}.scores small{display:block;font-size:10px;color:#89947f;margin-bottom:7px}.scores strong{font-size:25px;font-weight:650;font-variant-numeric:tabular-nums;line-height:1}.board-wrap{position:relative}.board{display:grid;grid-template-columns:repeat(4,1fr);gap:10px;background:#d7ddcb;padding:12px;border-radius:17px;aspect-ratio:1;touch-action:none;outline:none}.board:focus-visible{box-shadow:0 0 0 3px var(--green)}.cell{border-radius:9px;background:#e5e8db;display:grid;place-items:center;color:#4b5940;font-size:42px;font-weight:600;font-variant-numeric:tabular-nums;user-select:none}.cell[data-v="2"]{background:#f3f1e4}.cell[data-v="4"]{background:#e7e8cc}.cell[data-v="8"]{background:#cadba8}.cell[data-v="16"]{background:#abc88d}.cell[data-v="32"]{background:#8db478;color:#fff}.cell[data-v="64"]{background:#6f9e69;color:#fff}.cell[data-v="128"]{background:#53855f;color:#fff;font-size:35px}.cell[data-v="256"]{background:#3d7155;color:#fff;font-size:35px}.cell[data-v="512"]{background:#315b49;color:#e5f0cd;font-size:35px}.cell[data-v="1024"],.cell[data-v="2048"],.cell.high{background:#254638;color:#e5efb7;font-size:29px}.cell.pop{animation:grow .16s ease-out}@keyframes grow{from{transform:scale(.88);opacity:.6}to{transform:scale(1);opacity:1}}button{border:0;border-radius:8px;background:var(--ink);color:#f8faed;font:inherit;font-size:12px;padding:14px 20px;cursor:pointer;transition:background .15s,transform .15s}button:hover{background:#3e624f}button:active{transform:translateY(1px)}button:focus-visible{outline:3px solid #84a36d;outline-offset:3px}.toolbar{display:flex;justify-content:space-between;margin-top:15px}.toolbar button{min-width:132px}.toolbar button span{margin-left:25px}.secondary{color:#65745d;border:1px solid #d5dccb;background:transparent}.secondary:hover{background:#e7ebdc}button:disabled{opacity:.4;cursor:default;transform:none}.status{text-align:center;font-size:11px;color:#7d8c70;min-height:16px;margin:16px 0 24px}.tip{border-top:1px solid var(--line);padding-top:18px;display:flex;gap:20px;align-items:center;font-size:11px}.tip span{color:#506d42;white-space:nowrap}.tip p{margin:0;color:#8a9580;line-height:1.8}footer{border-top:1px solid var(--line);min-height:82px;color:#85917d;font-size:10px}footer span:last-child{font-size:9px;letter-spacing:1.5px}.overlay{position:absolute;inset:0;border-radius:17px;background:#f5f3ebed;display:grid;place-items:center;text-align:center;padding:24px;backdrop-filter:blur(3px)}[hidden]{display:none!important}.overlay #end-icon{font-size:48px;color:var(--green)}.overlay h2{font-size:24px;font-weight:600}.overlay p{font-size:12px;color:#7b886d;line-height:2}.overlay button{margin:8px 4px}dialog{border:1px solid var(--line);border-radius:18px;padding:28px;max-width:calc(100% - 32px);background:var(--paper);color:var(--ink)}dialog::backdrop{background:#20362c66}dialog h2{font-size:20px}dialog p{font-size:13px;color:#738069;line-height:1.8}dialog form>div{display:flex;gap:10px;justify-content:flex-end;margin-top:25px}@media(max-width:1280px){header,footer{margin-inline:40px}main{margin-inline:70px;grid-template-columns:minmax(0,1fr) 430px;gap:70px}h1{font-size:60px}}@media(max-width:900px){header,footer{margin-inline:25px}main{margin:38px auto 35px;max-width:470px;display:flex;flex-direction:column;gap:26px;padding:0 20px}header{height:75px}.intro .how,.game-name,.quiet{display:none}h1{font-size:40px;line-height:1.2;margin:15px 0 13px;letter-spacing:-1px}h1 br{display:none}.eyebrow{font-size:9px}.lede{font-size:12px;margin:0}.lede br{display:none}.header-note{font-size:10px;letter-spacing:1px}.play{width:100%}.cell{font-size:36px}.scores strong{font-size:22px}.scores{gap:16px}.tip{gap:14px}footer{font-size:9px;min-height:65px}footer span:last-child{font-size:7px;letter-spacing:.7px}}@media(max-width:380px){main{padding:0 16px;margin-top:24px}h1{font-size:34px}.board{padding:9px;gap:7px}.cell{font-size:30px}.cell[data-v="128"],.cell[data-v="256"],.cell[data-v="512"]{font-size:27px}.cell[data-v="1024"],.cell[data-v="2048"],.cell.high{font-size:22px}.title-small{font-size:11px}.brand{font-size:11px}.toolbar button{min-width:120px}footer span:last-child{display:none}}@media(prefers-reduced-motion:reduce){*,*::before,*::after{animation:none!important;transition:none!important}}