:root{--bg: #0f172a;--panel: #1e293b;--panel2: #273449;--text: #e2e8f0;--accent: #38bdf8;--accent-ink: #082f49;--muted: #94a3b8;--border: #334155}*{box-sizing:border-box}html,body{margin:0;background:var(--bg);color:var(--text);font-family:system-ui,-apple-system,Segoe UI,sans-serif;-webkit-tap-highlight-color:transparent;overscroll-behavior:none}#app{display:flex;justify-content:center}.app{width:100%;max-width:480px;padding:14px;display:flex;flex-direction:column;align-items:center;gap:14px;min-height:100dvh}header{width:100%;display:flex;justify-content:space-between;align-items:center}.brand{font-weight:800;font-size:24px;letter-spacing:.5px}.meta{display:flex;gap:12px;align-items:center;color:var(--muted);font-variant-numeric:tabular-nums}.icon{width:32px;height:32px;border-radius:8px;border:1px solid var(--border);background:var(--panel);color:var(--text);font-size:15px;cursor:pointer}.archive-note{color:var(--muted);font-size:13px}canvas{border-radius:16px;background:var(--bg);touch-action:none;transition:box-shadow .4s ease}.solved-board{box-shadow:0 0 0 2px var(--accent),0 0 32px #38bdf859}.actions{display:flex;gap:12px}.actions button,.primary{background:var(--panel);color:var(--text);border:1px solid var(--border);padding:11px 20px;border-radius:10px;font-size:15px;cursor:pointer}.actions button:active{background:var(--panel2)}.primary{background:var(--accent);color:var(--accent-ink);border:none;font-weight:700}.post-solve{display:flex;flex-direction:column;align-items:center;gap:8px}.next{color:var(--muted);font-size:13px;font-variant-numeric:tabular-nums}footer{color:var(--muted);font-size:12px;text-align:center;max-width:320px;margin-top:auto}.loading{padding:60px;color:var(--muted)}.toast{position:fixed;bottom:24px;left:50%;transform:translate(-50%);background:var(--panel2);color:var(--text);padding:10px 18px;border-radius:10px;border:1px solid var(--border);font-size:14px;box-shadow:0 6px 24px #0006}.overlay{position:fixed;top:0;right:0;bottom:0;left:0;background:#020617b3;display:flex;align-items:flex-end;justify-content:center;z-index:10;animation:fade .18s ease}.overlay-card{background:var(--panel);border:1px solid var(--border);border-radius:18px 18px 0 0;padding:24px;width:100%;max-width:480px;animation:slideup .22s ease}@media(min-width:520px){.overlay{align-items:center}.overlay-card{border-radius:18px}}@keyframes fade{0%{opacity:0}}@keyframes slideup{0%{transform:translateY(40px);opacity:0}}.win{display:flex;flex-direction:column;align-items:center;gap:12px;text-align:center}.confetti{font-size:48px;animation:pop .5s ease}@keyframes pop{0%{transform:scale(.3)}60%{transform:scale(1.25)}to{transform:scale(1)}}.win-title{font-size:26px;font-weight:800}.win-stats{display:flex;gap:18px;color:var(--muted);font-size:17px;font-variant-numeric:tabular-nums}.upsell{color:var(--accent);font-size:14px;text-decoration:none;margin-top:4px}.sheet h2{margin:0 0 14px;font-size:20px}.sheet ul{margin:0 0 18px;padding-left:20px;line-height:1.7;color:var(--text)}.sheet .row{display:flex;justify-content:space-between;align-items:center;padding:12px 0;border-bottom:1px solid var(--border)}.sheet .row input{width:20px;height:20px;accent-color:var(--accent)}.sheet .primary{margin-top:16px;width:100%}@media(prefers-reduced-motion:reduce){.confetti,.overlay,.overlay-card{animation:none}canvas{transition:none}}