:root{--bg:#0d1224;--panel:#171d35;--grid:#252d4c;--slot:#151b31;--cyan:#50c7f5;--violet:#8a75f5;--coral:#f06f7e;--gold:#ffc857;--text:#f5f7ff;--sub:#9aa5c1;--safe-top:env(safe-area-inset-top,0px);--safe-bottom:env(safe-area-inset-bottom,0px)}*{box-sizing:border-box}html,body{min-width:320px;min-height:100%;margin:0;background:radial-gradient(circle at 50% 0,rgba(80,199,245,.12),transparent 35%),var(--bg);color:var(--text);font-family:Inter,ui-rounded,"SF Pro Rounded",system-ui,sans-serif;overscroll-behavior:none;user-select:none}button{font:inherit}#shell{width:min(500px,100%);min-height:100vh;margin:auto;padding:calc(18px + var(--safe-top)) 16px calc(24px + var(--safe-bottom))}#backBtn{width:42px;height:42px;padding:0 0 4px;border:1px solid rgba(255,255,255,.14);border-radius:14px;background:#171d35;color:#fff;font-size:31px;line-height:1}header{display:flex;align-items:end;justify-content:space-between;margin:18px 2px 12px}h1{margin:2px 0 0;font-size:31px;letter-spacing:-.05em}h1 em{color:var(--gold);font-style:normal}.eyebrow{color:var(--cyan);font-size:8px;font-weight:1000;letter-spacing:.18em}#newBtn{min-height:40px;padding:0 14px;border:1px solid rgba(255,255,255,.13);border-radius:12px;background:var(--panel);color:var(--sub);font-size:9px;font-weight:1000;letter-spacing:.12em}.scorebar{display:grid;grid-template-columns:1fr 1fr auto;gap:8px;margin-bottom:10px}.scorebar>div{position:relative;padding:9px 11px;border:1px solid rgba(255,255,255,.08);border-radius:13px;background:var(--panel)}.scorebar small{display:block;color:var(--sub);font-size:7px;font-weight:950;letter-spacing:.13em}.scorebar strong{font-size:17px}.scorebar #modePill{display:grid;place-items:center;color:var(--cyan);font-size:8px;font-weight:1000;letter-spacing:.1em}#scoreAdd{position:absolute;right:10px;top:9px;color:var(--gold);font-size:11px;font-style:normal;animation:rise .6s forwards}#combo{margin:0 0 9px;padding:7px 12px;border:1px solid rgba(255,200,87,.25);border-radius:12px;background:rgba(255,200,87,.08);color:#ffe099;text-align:center;font-size:8px;font-weight:1000;letter-spacing:.11em}#combo b{margin-left:5px;font-size:12px}.hidden{display:none!important}
#board{aspect-ratio:1;display:grid;grid-template-columns:repeat(4,1fr);grid-template-rows:repeat(4,1fr);gap:9px;padding:9px;border:1px solid rgba(255,255,255,.1);border-radius:22px;background:var(--grid);box-shadow:0 22px 50px rgba(0,0,0,.3);touch-action:none}.cell{display:grid;place-items:center;border-radius:14px;background:var(--slot);font-size:clamp(20px,8vw,35px);font-weight:1000;letter-spacing:-.04em;box-shadow:inset 0 1px rgba(255,255,255,.04);transition:transform .11s ease,background .15s,color .15s}.cell.new{animation:pop .18s ease-out}.cell.merged{animation:merge .23s ease-out}.v2{background:#263c68;color:#8edfff}.v4{background:#33478f;color:#c6d4ff}.v8{background:#6544a8;color:#eee5ff}.v16{background:#a04883;color:#ffe5f6}.v32{background:#c65373;color:#fff}.v64{background:#e66c61;color:#fff}.v128{background:#e58d51;color:#fff4df;font-size:clamp(18px,7vw,30px)}.v256{background:#e6ad45;color:#fff9dd;font-size:clamp(18px,7vw,30px)}.v512{background:#edc654;color:#342608;font-size:clamp(18px,7vw,30px)}.v1024{background:#ffd86b;color:#362800;font-size:clamp(15px,6vw,25px)}.v2048,.v4096,.v8192{background:linear-gradient(145deg,#fff0a3,#ffb62d);color:#392500;font-size:clamp(15px,6vw,25px);box-shadow:0 0 26px rgba(255,200,87,.45)}.instruction{margin:14px 8px;color:var(--sub);font-size:11px;line-height:1.5;text-align:center}.instruction b{color:var(--gold)}
.overlay{position:fixed;z-index:20;inset:0;display:grid;place-items:center;padding:20px;background:rgba(7,10,22,.72);backdrop-filter:blur(7px)}.panel{width:min(390px,100%);padding:27px 22px 22px;border:1px solid rgba(255,255,255,.12);border-radius:25px;background:linear-gradient(150deg,#202942,#11172b);box-shadow:0 30px 80px rgba(0,0,0,.5);text-align:center}.panel.compact{max-width:340px}.panel h2{margin:8px 0;font-size:26px}.panel p{margin:0 auto 18px;color:var(--sub);font-size:12px;line-height:1.5}.primary,.secondary{width:100%;min-height:54px;border:0;border-radius:15px;font-weight:1000;letter-spacing:.07em}.primary{background:linear-gradient(135deg,#63d7ff,#4b9df5);color:#071528;box-shadow:0 7px 0 #2765aa}.secondary{margin-top:13px;border:1px solid rgba(255,255,255,.12);background:#252d4c;color:#fff}.primary small,.secondary small{display:block;margin-top:2px;font-size:8px;font-weight:700;opacity:.7}#messageIcon{font-size:36px}@keyframes pop{0%{transform:scale(.45);opacity:.2}70%{transform:scale(1.08)}}@keyframes merge{50%{transform:scale(1.13)}}@keyframes rise{to{transform:translateY(-18px);opacity:0}}@media(max-height:690px){#shell{padding-top:calc(9px + var(--safe-top))}#backBtn{width:36px;height:36px}header{margin:9px 2px}h1{font-size:27px}.scorebar>div{padding:6px 9px}#board{gap:7px;padding:7px}.instruction{margin-top:8px}}