:root{--lightningcss-light: ;--lightningcss-dark:initial;color-scheme:dark;--bg:#0f172a;--surface:#1e293b;--surface-raised:#273449;--border:#334155;--text:#f1f5f9;--text-muted:#94a3b8;--accent:#38bdf8;--accent-contrast:#082f49;--radius:12px;font-family:system-ui,-apple-system,Segoe UI,Roboto,Helvetica Neue,Arial,sans-serif;line-height:1.5}*{box-sizing:border-box}html,body{background:var(--bg);min-height:100%;color:var(--text);margin:0}body{padding:env(safe-area-inset-top) env(safe-area-inset-right) env(safe-area-inset-bottom) env(safe-area-inset-left)}.app{flex-direction:column;gap:16px;width:min(100%,720px);margin:0 auto;padding:16px;display:flex}.app__header h1{margin:0;font-size:1.75rem}.app__header p,.app__hint{color:var(--text-muted);margin:4px 0 0}.app__main{flex-direction:column;gap:16px;display:flex}.size-picker{border:0;margin:0;padding:0}.size-picker legend{margin-bottom:8px;padding:0;font-weight:600}.size-picker__options{grid-template-columns:repeat(auto-fit,minmax(64px,1fr));gap:8px;display:grid}.size-picker__option{display:block;position:relative}.size-picker__option input{opacity:0;cursor:pointer;margin:0;position:absolute;inset:0}.size-picker__option span{text-align:center;background:var(--surface);border:2px solid var(--border);border-radius:var(--radius);padding:12px 0;font-weight:600;display:block}.size-picker__option input:checked+span{background:var(--accent);border-color:var(--accent);color:var(--accent-contrast)}.size-picker__option input:focus-visible+span{outline:3px solid var(--text);outline-offset:2px}.cube-view{aspect-ratio:1;background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);width:100%;max-height:70vh;overflow:hidden}.cube-view twisty-player{width:100%;height:100%}.flat-cube{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);width:100%;height:auto;padding:8px;display:block}.playground{flex-direction:column;gap:12px;display:flex}.playground h2{margin:0;font-size:1.25rem}.playground__label{color:var(--text-muted);font-size:.9rem}.playground__input{width:100%;font:inherit;color:var(--text);background:var(--surface);border:2px solid var(--border);border-radius:var(--radius);padding:12px;font-family:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace}.playground__input:focus-visible{outline:3px solid var(--accent);outline-offset:2px}.playground__input[aria-invalid=true]{border-color:#f87171}.playground__ok,.playground__error{min-height:1.5em;margin:0}.playground__ok{color:var(--text-muted)}.playground__error{color:#fca5a5}.playground__steps{color:var(--text-muted);flex-direction:column;gap:4px;margin:0;padding-left:1.5rem;display:flex}.playground__steps strong{color:var(--text);font-family:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace}button,select{font:inherit;color:var(--text)}button{background:var(--surface-raised);border:2px solid var(--border);border-radius:var(--radius);cursor:pointer;min-height:48px;padding:12px 16px}button:hover:not(:disabled){border-color:var(--accent)}button:focus-visible,select:focus-visible,input[type=range]:focus-visible,summary:focus-visible{outline:3px solid var(--accent);outline-offset:2px}button:disabled{opacity:.45;cursor:not-allowed}.button--primary{background:var(--accent);border-color:var(--accent);color:var(--accent-contrast);font-weight:700}.visually-hidden{clip-path:inset(50%);white-space:nowrap;width:1px;height:1px;position:absolute;overflow:hidden}.editor,.solution,.solving{flex-direction:column;gap:12px;display:flex}.editor h2,.solution h2,.solving h2{margin:0;font-size:1.25rem}.editor__intro,.editor__hint,.solution__hold,.solution__stage{color:var(--text-muted);margin:0}.editor__hint{font-size:.9rem}.solution__hold,.solution__stage{text-align:center}.solving__note{color:var(--text-muted);margin:0}.editor__actions,.solution__footer{flex-wrap:wrap;gap:8px;display:flex}.editor__actions button,.solution__footer button{flex:140px}.flat-cube--editable g[role=button]{cursor:pointer}.flat-cube--editable g[role=button]:hover rect{stroke:#fff;stroke-width:1.2px}.flat-cube--editable g[role=button]:focus-visible{outline:none}.flat-cube--editable g[role=button]:focus-visible rect{stroke:var(--accent);stroke-width:1.6px}.palette{border:0;margin:0;padding:0}.palette legend{margin-bottom:8px;padding:0;font-weight:600}.palette__options{grid-template-columns:repeat(auto-fit,minmax(92px,1fr));gap:8px;display:grid}.palette__option{background:var(--surface);border:2px solid var(--border);border-radius:var(--radius);cursor:pointer;align-items:center;gap:8px;min-height:44px;padding:8px 10px;display:flex;position:relative}.palette__option input{opacity:0;cursor:pointer;margin:0;position:absolute;inset:0}.palette__option:has(input:checked){border-color:var(--accent);background:var(--surface-raised)}.palette__option:has(input:focus-visible){outline:3px solid var(--text);outline-offset:2px}.palette__swatch{border:1px solid #0f172a;border-radius:6px;flex:none;width:22px;height:22px}.message{border-radius:var(--radius);border:1px solid var(--border);background:var(--surface);margin:0;padding:10px 12px}.message p{margin:0 0 4px}.message ul{margin:0;padding-left:1.25rem}.message--error{color:#fecaca;border-color:#f87171}.message--warning{border-color:#fbbf24}.message--info{color:var(--text-muted)}.spinner{border:4px solid var(--border);border-top-color:var(--accent);border-radius:50%;width:40px;height:40px;animation:.9s linear infinite spin}@keyframes spin{to{transform:rotate(360deg)}}@media (prefers-reduced-motion:reduce){.spinner{animation-duration:3s}*{scroll-behavior:auto!important;transition-duration:.01ms!important}}.skip-link{z-index:10;color:var(--accent-contrast);background:var(--accent);border-radius:var(--radius);padding:10px 16px;font-weight:700;position:absolute;top:-100px;left:8px}.skip-link:focus{top:8px}main:focus{outline:none}input:focus-visible,a:focus-visible,[tabindex]:focus-visible{outline:3px solid var(--accent);outline-offset:2px}.step{text-align:center;background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);min-height:9rem;padding:12px}.step p{margin:0}.step__count{color:var(--text-muted)}.step__badge{color:var(--accent);font-family:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;font-size:3rem;font-weight:800;line-height:1.2}.step__hint,.step__done{font-size:1.1rem}.solution__progress{width:100%;accent-color:var(--accent);touch-action:pan-y;min-height:44px;margin:0}.solution__controls{grid-template-columns:repeat(5,minmax(0,1fr));gap:8px;display:grid}.solution__controls button{padding-inline:4px}.solution__speed{color:var(--text-muted);align-items:center;gap:8px;display:flex}.solution__speed select{background:var(--surface);border:2px solid var(--border);border-radius:var(--radius);min-height:44px;padding:8px 10px}.solution h2:focus{outline:none}.step__count{font-variant-numeric:tabular-nums}.solution__goto{color:var(--text-muted);flex-direction:column;gap:6px;display:flex}.solution__goto-row{gap:8px;display:flex}.solution__goto input{min-width:0;min-height:48px;font:inherit;color:var(--text);background:var(--surface);border:2px solid var(--border);border-radius:var(--radius);flex:auto;padding:8px 12px}.solution__goto input[aria-invalid=true]{border-color:#f87171}.solution__goto button{flex:none;min-width:72px}.stages h3,.solution__moves h3{margin:0 0 8px;font-size:1rem}.stages__list{flex-direction:column;gap:8px;margin:0;padding:0;list-style:none;display:flex}.stages__button{text-align:left;flex-direction:column;align-items:flex-start;gap:2px;width:100%;display:flex}.stages__range{color:var(--text-muted);font-size:.9rem}.stages__button--active{border-color:var(--accent);background:var(--accent);color:var(--accent-contrast)}.stages__button--active .stages__range{color:var(--accent-contrast);font-weight:700}.movelist{overscroll-behavior:contain;background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);overflow-y:auto}.movelist:focus-visible{outline:3px solid var(--accent);outline-offset:2px}.movelist__list{margin:0;padding:0;list-style:none;position:relative}.movelist__row{padding:2px 4px;position:absolute;left:0;right:0}.movelist__move{text-align:left;background:0 0;border-width:2px;align-items:center;gap:12px;width:100%;height:100%;min-height:0;padding:0 12px;display:flex}.movelist__number{min-width:3ch;color:var(--text-muted);font-variant-numeric:tabular-nums}.movelist__notation{font-family:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;font-size:1.1rem;font-weight:700}.movelist__stage{color:var(--text-muted);margin-left:auto;font-size:.85rem}.movelist__row--alg .movelist__move{border-left:6px solid var(--accent)}.movelist__alg{min-width:0;color:var(--text);text-overflow:ellipsis;white-space:nowrap;margin-left:auto;font-size:.85rem;font-weight:600;overflow:hidden}.movelist__alg+.movelist__stage{margin-left:8px}.movelist__move--done .movelist__notation{color:var(--text-muted);font-weight:400}.movelist__move--current{border-color:var(--accent);background:var(--accent);color:var(--accent-contrast)}.movelist__move--current .movelist__number,.movelist__move--current .movelist__alg,.movelist__move--current .movelist__stage{color:var(--accent-contrast)}.solution__shortcuts{flex-direction:column;gap:6px;margin:8px 0 0;padding-left:1.25rem;display:flex}kbd{color:var(--text);background:var(--surface-raised);border:1px solid var(--border);border-radius:6px;padding:1px 6px;font-family:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;font-size:.9em}.solution__legend{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);color:var(--text-muted);padding:10px 12px}.solution__legend summary{cursor:pointer;min-height:44px;color:var(--text);align-items:center;font-weight:600;display:flex}.solution__legend table{border-collapse:collapse;margin:8px 0}.solution__legend th,.solution__legend td{text-align:left;padding:4px 12px 4px 0}.legend__swatch{vertical-align:-2px;border:1px solid #0f172a;border-radius:3px;width:14px;height:14px;margin-right:6px;display:inline-block}.primer__title{color:var(--text);margin:12px 0 4px;font-size:1rem}.primer__examples{flex-direction:column;gap:6px;margin:8px 0;padding-left:1.25rem;display:flex}.primer code{color:var(--text);background:var(--surface-raised);border:1px solid var(--border);border-radius:6px;padding:1px 6px;font-weight:700}.learn__toggle{flex-direction:column;gap:4px;display:flex}.learn__toggle label{align-items:center;gap:10px;min-height:44px;font-weight:600;display:flex}.learn__toggle input{width:24px;height:24px}.learn__toggle p{color:var(--text-muted);margin:0}.learn__what{color:var(--text);font-weight:600}.learn__replay{margin-top:4px}.learn__alg{background:var(--surface-raised);border:1px solid var(--border);border-left:6px solid var(--accent);border-radius:var(--radius);padding:8px 12px}.learn__alg p{margin:4px 0 0}.learn__alg-name{color:var(--text);font-weight:700}.learn__algs{margin:4px 0 0;padding-left:1.25rem}.editor__teach{flex-direction:column;gap:4px;display:flex}.editor__teach label{align-items:center;gap:10px;min-height:44px;font-weight:600;display:flex}.editor__teach input{width:24px;height:24px}.editor__teach p{color:var(--text-muted);margin:0;font-size:.9rem}.scan{flex-direction:column;gap:12px;display:flex}.scan h2{margin:0;font-size:1.25rem}.scan__step,.scan__instruction,.scan__tip{margin:0}.scan__instruction,.scan__tip{color:var(--text-muted)}.scan__net{align-self:center;width:min(100%,260px)}.scan__net-face{fill:var(--surface);stroke:var(--border);stroke-width:.6px}.scan__net-active{fill:var(--accent);stroke:#fff;stroke-width:.8px}.scan__net-label{fill:var(--text);pointer-events:none}.scan__net-active+.scan__net-label{fill:var(--accent-contrast);font-weight:700}.scan__camera{aspect-ratio:1;border:1px solid var(--border);border-radius:var(--radius);background:#000;width:min(100%,70vh);margin-inline:auto;position:relative;overflow:hidden}.scan__video{object-fit:cover;width:100%;height:100%}.scan__grid{pointer-events:none;border:2px solid #fffffff2;display:grid;position:absolute;inset:14%}.scan__grid span{border:1px solid #ffffffbf}.scan__starting{text-align:center;color:#fff;margin:0;position:absolute;inset:auto 0 12px}.scan__thumbs{grid-template-columns:repeat(6,minmax(0,1fr));gap:6px;margin:0;padding:0;list-style:none;display:grid}.scan__thumb{flex-direction:column;align-items:center;gap:4px;width:100%;min-height:0;padding:6px 2px;font-size:.75rem;display:flex}.scan__thumb[aria-current=step]{border-color:var(--accent)}.scan__thumb img,.scan__thumb-empty{aspect-ratio:1;object-fit:cover;border-radius:6px;width:100%;max-width:48px}.scan__thumb-empty{background:var(--surface);border:1px dashed var(--border);color:var(--text-muted);place-items:center;display:grid}.scan__working{color:var(--text-muted);margin:0}.scan__actions{gap:8px;display:flex}