:root{--lightningcss-light: ;--lightningcss-dark:initial;color-scheme:dark;color:#f5f7ff;font-synthesis:none;background:#090d1f;font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Noto Sans,Ubuntu,Cantarell,Helvetica Neue,sans-serif}*{box-sizing:border-box}body{--bg:#090d1f;--surface:rgba(21,28,60,.82);--surface-strong:#161e42;--border:rgba(139,163,255,.22);--text:#f5f7ff;--muted:#a7b0d3;--accent:#78d7ff;--accent-2:#8c7bff;--board:rgba(10,15,37,.72);--cell:rgba(125,143,210,.13);--tile-high-text:#fff;--tile-2:#c4d3ff;--tile-2-text:#252c52;--tile-4:#c5e5ff;--tile-4-text:#19334d;--tile-8:#21749b;--tile-16:#177966;--tile-32:#6854d9;--tile-64:#9027b2;--tile-128:#a71f5d;--tile-256:#b33225;--tile-512:#177888;--tile-1024:#356fa9;--tile-2048:#8f6900;--tile-super:#5542c2;--shadow:0 24px 80px rgba(0,0,0,.36);background:radial-gradient(circle at 10% 10%, rgba(80,112,255,.2), transparent 34rem), radial-gradient(circle at 90% 30%, rgba(65,211,255,.13), transparent 30rem), var(--bg);min-width:320px;min-height:100vh;color:var(--text);margin:0}body[data-theme=classic]{--lightningcss-light:initial;--lightningcss-dark: ;color-scheme:light;--bg:#faf8ef;--surface:rgba(255,255,255,.88);--surface-strong:#f3efe5;--border:rgba(119,110,101,.2);--text:#625b52;--muted:#857a70;--accent:#edc53f;--accent-2:#f59b68;--board:#bbada0;--cell:rgba(238,228,218,.5);--tile-2:#eee4da;--tile-2-text:#544b43;--tile-4:#ede0c8;--tile-4-text:#544b43;--tile-8:#ad5b28;--tile-16:#b95529;--tile-32:#b9432d;--tile-64:#aa331d;--tile-128:#8c6a19;--tile-256:#85610c;--tile-512:#795500;--tile-1024:#735000;--tile-2048:#694700;--tile-super:#3c3a32;--shadow:0 24px 70px rgba(83,66,49,.15);background:var(--bg)}body[data-theme=kawaii]{--bg:#fff2f7;--surface:rgba(255,255,255,.88);--surface-strong:#fff8fb;--border:rgba(246,132,181,.25);--text:#633a54;--muted:#9a6a83;--accent:#ff8fbe;--accent-2:#ad8cff;--board:rgba(242,164,198,.35);--cell:rgba(255,255,255,.55);--tile-2:#ffb4d6;--tile-2-text:#5b2540;--tile-4:#ffabd2;--tile-4-text:#5b2540;--tile-8:#a9336b;--tile-16:#a52b61;--tile-32:#a23470;--tile-64:#84316e;--tile-128:#78358d;--tile-256:#623b9b;--tile-512:#41449a;--tile-1024:#15406f;--tile-2048:#226886;--tile-super:#285f82;--shadow:0 24px 70px rgba(176,95,133,.2);background:radial-gradient(circle at 12% 12%, rgba(255,169,207,.32), transparent 34rem), var(--bg)}button,input{font:inherit}button,a{-webkit-tap-highlight-color:transparent}button:focus-visible{outline:3px solid color-mix(in srgb, var(--accent), white 25%);outline-offset:3px}a:focus-visible{outline:3px solid color-mix(in srgb, var(--accent), white 25%);outline-offset:3px}input:focus-visible{outline:3px solid color-mix(in srgb, var(--accent), white 25%);outline-offset:3px}.game-shell{width:min(1100px,100% - 32px);margin:0 auto;padding:22px 0 64px}.topbar,.hero,.score-row,.game-layout{display:flex}.topbar{justify-content:space-between;align-items:center;gap:16px;margin-bottom:42px}.topbar-actions{flex-wrap:wrap;justify-content:flex-end;gap:8px;display:flex}.home-link,.quiet-button{border:1px solid var(--border);background:color-mix(in srgb, var(--surface), transparent 15%);color:var(--text);cursor:pointer;border-radius:999px;padding:10px 15px;text-decoration:none;transition:transform .16s,border-color .16s}.home-link:hover,.quiet-button:hover{border-color:var(--accent);transform:translateY(-1px)}.hero{justify-content:space-between;align-items:flex-end;gap:28px;margin-bottom:28px}.eyebrow{color:var(--accent);letter-spacing:.16em;margin:0 0 8px;font-size:.76rem;font-weight:800}h1{letter-spacing:-.08em;background:linear-gradient(135deg, var(--accent), var(--accent-2));color:transparent;-webkit-background-clip:text;background-clip:text;margin:0;font-size:max(4.5rem,min(13vw,8.4rem));line-height:.82}.intro{max-width:600px;color:var(--muted);margin:24px 0 0;font-size:1.05rem;line-height:1.7}.status-card{border:1px solid var(--border);background:var(--surface);min-width:280px;box-shadow:var(--shadow);-webkit-backdrop-filter:blur(18px);backdrop-filter:blur(18px);border-radius:18px;align-items:center;gap:13px;padding:17px 19px;display:flex}.status-card div{gap:3px;display:grid}.status-card span:last-child{color:var(--muted);font-size:.83rem}.status-dot{background:#63df9b;border-radius:50%;flex:none;width:11px;height:11px;box-shadow:0 0 0 5px rgba(99,223,155,.12)}.status-dot.syncing{background:#ffd36e;animation:1.2s infinite pulse}.status-dot.offline,.status-dot.error{background:#ff8a9b;box-shadow:0 0 0 5px rgba(255,138,155,.12)}@keyframes pulse{50%{opacity:.45}}.score-row{grid-template-columns:repeat(4,minmax(0,1fr));gap:12px;margin-bottom:16px;display:grid}.score-card{border:1px solid var(--border);background:var(--surface);border-radius:15px;gap:5px;padding:14px 16px;display:grid}.score-card span{color:var(--muted);text-transform:uppercase;letter-spacing:.08em;font-size:.78rem}.score-card strong{font-size:1.5rem}.game-layout{grid-template-columns:minmax(300px,1fr) 310px;align-items:start;gap:18px;display:grid}.board-wrap{position:relative}.board{--board-gap:clamp(8px, 1.5vw, 13px);--board-padding:clamp(9px, 1.8vw, 15px);aspect-ratio:1;padding:var(--board-padding);border:1px solid var(--border);background:var(--board);box-shadow:var(--shadow);touch-action:none;border-radius:22px;position:relative}.board-grid{gap:var(--board-gap);grid-template-rows:repeat(4,minmax(0,1fr));grid-template-columns:repeat(4,minmax(0,1fr));width:100%;height:100%;display:grid}.board-cell{background:var(--cell);min-width:0;box-shadow:inset 0 0 0 1px color-mix(in srgb, var(--border), transparent 35%);border-radius:15px}.tile-layer{inset:var(--board-padding);pointer-events:none;position:absolute}.tile{--tile-size:calc((100% - 3 * var(--board-gap)) / 4);width:var(--tile-size);height:var(--tile-size);background:var(--tile-super);color:var(--tile-high-text);letter-spacing:-.02em;box-shadow:inset 0 0 0 1px color-mix(in srgb, var(--border), transparent 35%);transform:translate(calc(var(--column) * (100% + var(--board-gap))), calc(var(--row) * (100% + var(--board-gap))));will-change:transform;border-radius:15px;place-items:center;font-family:Clear Sans,Helvetica Neue,Arial,sans-serif;font-size:max(2rem,min(7.2vw,3.5rem));font-weight:700;line-height:1;transition:background-color .16s,color .16s;display:grid;position:absolute;top:0;left:0}.tile-moving{animation:.12s ease-in-out both tile-move}.tile[data-digits="4"]{font-size:max(1.65rem,min(5.8vw,2.8rem))}.tile[data-digits="5"]{font-size:max(1.35rem,min(4.8vw,2.25rem))}.tile[data-digits="6"]{font-size:max(1.15rem,min(4vw,1.9rem))}.tile[data-digits="7"],.tile[data-digits="8"],.tile[data-digits="9"],.tile[data-digits="10"]{font-size:max(.85rem,min(3.1vw,1.5rem))}.tile[data-value="2"]{background:var(--tile-2);color:var(--tile-2-text)}.tile[data-value="4"]{background:var(--tile-4);color:var(--tile-4-text)}.tile[data-value="8"]{background:var(--tile-8)}.tile[data-value="16"]{background:var(--tile-16)}.tile[data-value="32"]{background:var(--tile-32)}.tile[data-value="64"]{background:var(--tile-64)}.tile[data-value="128"]{background:var(--tile-128)}.tile[data-value="256"]{background:var(--tile-256)}.tile[data-value="512"]{background:var(--tile-512)}.tile[data-value="1024"]{background:var(--tile-1024)}.tile[data-value="2048"]{background:var(--tile-2048)}.tile[data-super=true]{background:var(--tile-super)}@keyframes tile-move{0%{transform:translate(calc(var(--from-column) * (100% + var(--board-gap))), calc(var(--from-row) * (100% + var(--board-gap))))}to{transform:translate(calc(var(--to-column) * (100% + var(--board-gap))), calc(var(--to-row) * (100% + var(--board-gap))))}}.tile-merged{animation:.16s ease-in-out tile-merge}.tile-spawned{animation:.16s ease-out tile-spawn}@keyframes tile-merge{50%{scale:1.18}}@keyframes tile-spawn{0%{opacity:0;scale:0}}.game-overlay{background:color-mix(in srgb, var(--bg), transparent 15%);-webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);z-index:2;border-radius:22px;place-content:center;justify-items:center;gap:18px;font-size:2rem;display:grid;position:absolute;top:0;bottom:0;left:0;right:0}.control-card{border:1px solid var(--border);background:var(--surface);box-shadow:var(--shadow);border-radius:22px;gap:24px;padding:20px;display:grid}.button-grid{grid-template-columns:1fr 1fr;gap:10px;display:grid}.primary-button,.secondary-button{cursor:pointer;border-radius:12px;min-height:45px;padding:10px 14px;transition:transform .15s,filter .15s}.primary-button{background:linear-gradient(135deg, var(--accent), var(--accent-2));color:#10142d;border:0;font-weight:800}.secondary-button{border:1px solid var(--border);background:var(--surface-strong);color:var(--text)}.primary-button:hover,.secondary-button:hover{filter:brightness(1.06);transform:translateY(-1px)}.primary-button:disabled,.secondary-button:disabled{cursor:wait;opacity:.58;transform:none}.theme-picker{flex-wrap:wrap;align-items:center;gap:8px;display:flex}.theme-picker>span{width:100%;color:var(--muted);font-size:.82rem}.theme-chip{border:1px solid var(--border);color:var(--text);cursor:pointer;background:0 0;border-radius:999px;padding:7px 10px}.theme-chip.active{border-color:var(--accent);background:color-mix(in srgb, var(--accent), transparent 80%)}.instructions h2{margin:0 0 10px;font-size:1rem}.instructions p{color:var(--muted);margin:0;font-size:.9rem;line-height:1.6}.instructions .privacy-note{border-top:1px solid var(--border);color:var(--accent);margin-top:12px;padding-top:12px;font-size:.8rem}dialog{border:1px solid var(--border);background:var(--surface-strong);width:min(520px,100% - 28px);color:var(--text);box-shadow:var(--shadow);border-radius:22px}dialog::backdrop{-webkit-backdrop-filter:blur(7px);backdrop-filter:blur(7px);background:rgba(5,8,20,.76)}dialog form,.conflict-content{gap:17px;padding:10px;display:grid;position:relative}dialog h2,dialog h3,dialog p{margin:0}dialog p{color:var(--muted);line-height:1.55}dialog label{color:var(--muted);gap:7px;font-size:.84rem;display:grid}dialog input{border:1px solid var(--border);background:color-mix(in srgb, var(--bg), transparent 25%);width:100%;color:var(--text);border-radius:12px;padding:12px 13px}.dialog-close{border:1px solid var(--border);width:36px;height:36px;color:var(--text);cursor:pointer;background:0 0;border-radius:50%;font-size:1.3rem;position:absolute;top:-4px;right:-4px}.admin-note{text-align:center;font-size:.78rem}.form-error{color:#ff9cae;background:rgba(255,117,140,.1);border:1px solid rgba(255,117,140,.45);border-radius:10px;padding:10px;font-size:.84rem}.conflict-grid{grid-template-columns:1fr 1fr;gap:12px;display:grid}.conflict-grid article{border:1px solid var(--border);background:color-mix(in srgb, var(--bg), transparent 45%);border-radius:15px;gap:14px;padding:15px;display:grid}.conflict-grid dl{grid-template-columns:auto 1fr;gap:7px 12px;margin:0;font-size:.82rem;display:grid}.conflict-grid dt{color:var(--muted)}.conflict-grid dd{text-align:right;margin:0;font-weight:700}.toast{border:1px solid var(--border);background:var(--surface-strong);max-width:min(520px,100% - 28px);color:var(--text);box-shadow:var(--shadow);z-index:10;border-radius:999px;padding:12px 17px;position:fixed;bottom:24px;left:50%;transform:translate(-50%)}.full-width{width:100%}.hidden{display:none!important}@media (max-width:800px){.hero{align-items:start;display:grid}.status-card{min-width:0}.game-layout{grid-template-columns:1fr}.control-card{order:-1}}@media (max-width:540px){.game-shell{width:min(100% - 20px,1100px);padding-top:12px}.topbar{align-items:flex-start;margin-bottom:32px}.topbar-actions{max-width:65%}.score-row{grid-template-columns:1fr 1fr}.conflict-grid{grid-template-columns:1fr}.board{border-radius:16px}.tile,.board-cell{border-radius:10px}}@media (prefers-reduced-motion:reduce){*,:before,:after{scroll-behavior:auto!important;transition-duration:.01ms!important;animation-duration:.01ms!important}.tile{will-change:auto}}