:root{--ground: #ffffff;--panel: #ffffff;--ink: #15202e;--muted: #4f5b6b;--line: #dadfe6;--mark: #c2187a;--mark-soft: #c2187a1f;--body: #20242a;--c-red: #d0202e;--c-blue: #1f5fd6;--c-green: #00a24a;--display: "Barlow Condensed", "Arial Narrow", system-ui, sans-serif;--hand: "Caveat", "Bradley Hand", cursive;--radius-btn: 12px;--s: 54px;font-family:Atkinson Hyperlegible,system-ui,-apple-system,Segoe UI,sans-serif;color:var(--ink);background:var(--ground);-webkit-text-size-adjust:100%}:root[data-theme=dark]{--ground: #12171e;--panel: #1a212b;--ink: #eef2f7;--muted: #9aa6b6;--line: #2e3846;--mark: #ff4fb0;--mark-soft: #ff4fb030;--body: #0b0e12;color-scheme:dark}:root[data-theme=light]{color-scheme:light}@media(prefers-color-scheme:dark){:root:not([data-theme=light]){--ground: #12171e;--panel: #1a212b;--ink: #eef2f7;--muted: #9aa6b6;--line: #2e3846;--mark: #ff4fb0;--mark-soft: #ff4fb030;--body: 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svg{width:24px;height:24px;stroke:currentColor;fill:none;stroke-width:2;stroke-linecap:round;stroke-linejoin:round}.screen.home{gap:18px}.hero{display:grid;grid-template-columns:minmax(0,1fr) auto;align-items:end;gap:6px}.hero h2{font-size:clamp(2.5rem,11vw,3.4rem);line-height:.92}.hero .stage3d{--s: 26px;min-height:calc(var(--s) * 4.6);width:calc(var(--s) * 4.4)}.how{list-style:none;margin:0;padding:14px 0 0;border-top:2px solid var(--ink);display:grid;gap:14px}.how li{display:grid;grid-template-columns:46px minmax(0,1fr);gap:12px;align-items:center}.how .num{width:46px;height:46px;border-radius:9px;color:#fff;display:grid;place-items:center;font-family:var(--display);font-weight:800;font-size:1.9rem}.how strong{display:block;font-size:1.1rem}.how span{display:block;color:var(--muted);font-size:.95rem;line-height:1.35}.ways{display:grid;gap:10px;margin-top:6px}@media(max-width:599px)and (max-height:900px){.ways{margin-top:auto}}@media(min-width:900px){#app:has(.screen.home){max-width:1140px;padding:0 40px}.screen.home{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,.85fr);grid-template-rows:auto auto auto;column-gap:88px;row-gap:0;align-content:start;padding:clamp(16px,5vh,56px) 0 40px}.screen.home .hero{display:contents}.screen.home .hero h2{grid-column:1;grid-row:1;font-size:clamp(4.4rem,6vw,5.4rem);line-height:.9;margin:0 0 32px;align-self:end}.screen.home .hero .stage3d{grid-column:2;grid-row:1 / span 3;--s: 68px;width:auto;min-height:calc(var(--s) * 5.4);align-self:center}.screen.home .how{grid-column:1;grid-row:2;padding-top:28px;gap:26px}.screen.home .how li{grid-template-columns:56px minmax(0,1fr);gap:20px}.screen.home .how .num{width:56px;height:56px;border-radius:11px;font-size:2.3rem}.screen.home .how strong{font-size:1.3rem;margin-bottom:3px}.screen.home .how span{font-size:1.05rem;line-height:1.45}.screen.home .ways{grid-column:1;grid-row:3;align-self:start;margin-top:40px;gap:14px}.screen.home .ways .primary{min-height:66px;font-size:1.25rem}.screen.home .ways2{gap:14px}.screen.home .ways2 .btn{min-height:58px;font-size:1.05rem}.screen.home .linkbtn{font-size:1rem}}@media(min-width:900px)and (max-height:780px){.screen.home{padding:8px 0 16px}.screen.home .hero h2{font-size:4rem;margin-bottom:20px}.screen.home .how{padding-top:18px;gap:16px}.screen.home .ways{margin-top:24px;gap:10px}.screen.home .ways .primary{min-height:58px}.screen.home .ways2 .btn{min-height:52px}}.ways .primary{min-height:60px;font-size:1.15rem}.ways2{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:10px}.ways2 .btn{min-height:52px;font-size:1rem;padding:0 10px}.choices{display:grid;gap:10px}.choice{text-align:left;display:grid;grid-template-columns:44px 1fr;gap:4px 14px;align-items:center;padding:14px 16px;border-radius:16px;border:1.5px solid var(--line);background:var(--panel)}.choice strong{font-size:1.1rem}.choice span{grid-column:2;color:var(--muted);font-size:.95rem}.choice svg{grid-row:span 2;width:36px;height:36px;stroke:var(--ink);fill:none;stroke-width:1.8;stroke-linecap:round;stroke-linejoin:round}.choice:hover{border-color:var(--ink)}.stage3d{position:relative;display:grid;place-items:center;min-height:calc(var(--s) * 5.2);touch-action:none;user-select:none;-webkit-user-select:none}.scene{perspective:calc(var(--s) * 14);width:calc(var(--s) * 3);height:calc(var(--s) * 3);display:grid;place-items:center}.cube{position:relative;width:0;height:0;transform-style:preserve-3d}.cubie{position:absolute;left:calc(var(--s) * -.5);top:calc(var(--s) * -.5);width:var(--s);height:var(--s);transform-style:preserve-3d;will-change:transform}.cap{position:absolute;left:calc(var(--s) * -1.47);top:calc(var(--s) * -1.47);width:calc(var(--s) * 2.94);height:calc(var(--s) * 2.94);background:var(--body);border-radius:4%;pointer-events:none}.cf{position:absolute;inset:0;background:var(--body);border-radius:6%;backface-visibility:hidden}.cf-f{transform:translateZ(calc(var(--s) / 2))}.cf-b{transform:rotateY(180deg) translateZ(calc(var(--s) / 2))}.cf-r{transform:rotateY(90deg) translateZ(calc(var(--s) / 2))}.cf-l{transform:rotateY(-90deg) translateZ(calc(var(--s) / 2))}.cf-u{transform:rotateX(90deg) translateZ(calc(var(--s) / 2))}.cf-d{transform:rotateX(-90deg) translateZ(calc(var(--s) / 2))}.st{position:absolute;inset:7%;border-radius:12%;transition:opacity .25s,box-shadow .25s}.st.faded{opacity:.3}.cf:has(>.st.faded){background:#a7afb9}@media(prefers-color-scheme:dark){:root:not([data-theme=light]) .cf:has(>.st.faded){background:#4a525d}}:root[data-theme=dark] .cf:has(>.st.faded){background:#4a525d}.st.hl{box-shadow:0 0 0 calc(var(--s) * .07) var(--mark),0 0 calc(var(--s) * .3) var(--mark)}.arrow{position:absolute;left:calc(var(--s) * -1.5);top:calc(var(--s) * -1.5);width:calc(var(--s) * 3);height:calc(var(--s) * 3);pointer-events:none;opacity:0;transition:opacity .2s;backface-visibility:hidden}.arrow.on{opacity:1}.arrow svg{width:100%;height:100%;overflow:visible}.arrow .halo{fill:none;stroke:var(--ground);stroke-width:13;stroke-linecap:round;opacity:.9}.arrow .arc{fill:none;stroke:var(--ink);stroke-width:6;stroke-linecap:round}.arrow .head{stroke:var(--ground);stroke-width:3;paint-order:stroke}.arrow .head{fill:var(--ink)}.arrow.ccw svg{transform:scaleX(-1)}.arrow.half .arc,.arrow.half .halo{stroke-dasharray:10 7}.arrow.whole .arc{stroke:var(--mark)}.arrow.whole .head{fill:var(--mark)}.arrow-f{transform:translateZ(calc(var(--s) * 1.5 + 3px))}.arrow-b{transform:rotateY(180deg) translateZ(calc(var(--s) * 1.5 + 3px))}.arrow-r{transform:rotateY(90deg) translateZ(calc(var(--s) * 1.5 + 3px))}.arrow-l{transform:rotateY(-90deg) translateZ(calc(var(--s) * 1.5 + 3px))}.arrow-u{transform:rotateX(90deg) translateZ(calc(var(--s) * 1.5 + 3px))}.arrow-d{transform:rotateX(-90deg) translateZ(calc(var(--s) * 1.5 + 3px))}.home-cube{min-height:calc(var(--s) * 4.6)}.stages{display:grid;grid-template-columns:repeat(var(--n, 7),1fr);gap:4px}.stages button{border:0;height:30px;padding:0;background:transparent;display:flex;flex-direction:column;align-items:stretch;justify-content:flex-end;gap:3px;font-size:.75rem;color:var(--muted)}.stages i{display:block;height:8px;border-radius:2px;background:var(--line);position:relative;overflow:hidden}.stages i b{position:absolute;inset:0 auto 0 0;background:var(--ink);width:0}.stages button.now{color:var(--ink);font-weight:700}.goal{font-size:1.02rem;line-height:1.35;font-weight:700}.headtools{display:flex;align-items:center;justify-content:space-between;gap:10px}.headtools .modes button{min-height:36px}.headtools .btn.small{min-height:40px}.stage3d .turncount{position:absolute;left:0;top:4px;display:grid;pointer-events:none}.turncount b{font-family:var(--display);font-weight:800;font-size:clamp(3.4rem,15vw,4.6rem);line-height:.85;font-variant-numeric:tabular-nums}.turncount span{color:var(--muted);font-size:.85rem}.stage3d .coach{position:absolute;right:0;top:0;max-width:34%;font-family:var(--hand);font-weight:700;font-size:1.3rem;line-height:1;color:var(--mark);transform:rotate(-3deg);text-align:right;pointer-events:none}.upnext{display:flex;flex-wrap:wrap;align-items:center;gap:6px 8px;margin-top:-6px;padding-left:88px}.uplabel{font-size:.85rem;color:var(--muted)}.tile{min-width:34px;height:30px;padding:0 6px;border:2px solid var(--line);border-radius:8px;display:inline-flex;align-items:center;justify-content:center;font-family:var(--display);font-weight:800;font-size:1.15rem}.tile.end{border:0;font-family:inherit;font-weight:400;font-size:.85rem;color:var(--muted);padding:0}.goal small{display:block;font-weight:400;font-size:.9rem;color:var(--muted);margin-top:2px}.movebox{display:grid;grid-template-columns:auto 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.btn{min-height:64px}.controls svg{width:26px;height:26px;stroke:currentColor;fill:none;stroke-width:2.4;stroke-linecap:round;stroke-linejoin:round}details.why{border-top:1px solid var(--line);padding-top:10px}details.why summary{cursor:pointer;font-weight:700;min-height:32px}details.why p{margin-top:6px;color:var(--muted)}.algs{display:grid;gap:10px;margin-top:8px}.alg{padding-left:12px;border-left:3px solid var(--line)}.alg.now{border-color:var(--mark)}.alg code{font-family:inherit;font-weight:700;display:block;font-size:1.05rem}.alg p{font-size:.9rem}.modes{display:inline-flex;border:2px solid var(--ink);border-radius:12px;padding:3px;gap:3px}.modes button{border:0;background:transparent;min-height:38px;padding:0 14px;border-radius:9px;font-weight:700;color:var(--muted)}.modes button[aria-pressed=true]{background:var(--ink);color:var(--ground)}.payoff{text-align:left;display:grid;gap:16px;padding:12px 0}.payoff .big{font-family:var(--display);font-size:5.6rem;font-weight:800;line-height:.9}.compare{display:grid;grid-template-columns:auto 1fr;gap:10px 14px;align-items:center}.compare .barwrap{height:18px;border-radius:9px;background:var(--line);overflow:hidden}.compare .bar{height:100%;background:var(--ink);border-radius:9px}.compare .bar.short{background:var(--mark)}.net{display:grid;grid-template-columns:repeat(12,1fr);gap:3px;width:100%;max-width:480px}.net .cell{aspect-ratio:1;border-radius:6px;border:0;padding:0;background:#8d96a3;position:relative}.net .cell.center:after{content:"";position:absolute;inset:35%;border-radius:50%;background:#00000030}.net .cell.low{box-shadow:0 0 0 3px var(--ground),0 0 0 5px var(--mark)}.net .cell.err{box-shadow:0 0 0 3px var(--ground),0 0 0 6px var(--mark);animation:pulse 1.2s infinite}@keyframes pulse{50%{box-shadow:0 0 0 3px var(--ground),0 0 0 8px var(--mark)}}@media(prefers-reduced-motion:reduce){.net 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var(--line);background:var(--panel);padding:12px;font-size:1rem;resize:vertical}.examples{display:flex;flex-wrap:wrap;gap:8px}.cam{position:relative;width:100%;aspect-ratio:1;max-height:50dvh;margin:0 auto;border-radius:18px;overflow:hidden;background:#000}.cam video{width:100%;height:100%;object-fit:cover}.guide{position:absolute;left:50%;top:50%;width:72%;aspect-ratio:1;transform:translate(-50%,-50%);display:grid;grid-template-columns:repeat(3,1fr);gap:4%}.guide div{border:3px solid #ffffffd0;border-radius:12%;box-shadow:0 0 0 1px #0006}.guide div.c{border-style:dashed}.swatches{display:grid;grid-template-columns:repeat(6,1fr);gap:6px}.swatches .face{display:grid;grid-template-columns:repeat(3,1fr);gap:1px;padding:3px;border-radius:8px;border:2px solid var(--line);aspect-ratio:1}.swatches .face.now{border-color:var(--ink)}.swatches .face i{border-radius:2px;background:var(--line)}.howto{font-size:1.05rem;line-height:1.4;font-weight:700;min-height:2.8em}.timer{font-variant-numeric:tabular-nums;color:var(--muted)}.scanhint{min-height:1.5em;font-weight:700;color:var(--mark)}.guide div{position:relative;transition:border-color .15s}.guide i{position:absolute;left:50%;top:50%;width:34%;aspect-ratio:1;transform:translate(-50%,-50%);border-radius:50%;border:2px solid #fff;box-shadow:0 0 0 1px #0007}.cam.locked .guide div{border-color:var(--mark)}.cam.flash:after{content:"";position:absolute;inset:0;background:#fff;opacity:.6;animation:flash .26s ease-out forwards}@keyframes flash{to{opacity:0}}.holdmeter{position:absolute;left:14%;right:14%;bottom:14px;height:6px;border-radius:3px;background:#fff5;overflow:hidden}.holdmeter b{display:block;height:100%;width:0;background:#fff;transition:width .1s linear}.scanrow{display:grid;grid-template-columns:auto 1fr;gap:14px;align-items:center}.stage3d.mini{min-height:calc(var(--s) * 5);width:calc(var(--s) * 5)}.scanside{display:grid;gap:10px}.scanprog{display:grid;grid-template-columns:repeat(6,1fr);gap:5px}.scanprog .face{display:grid;grid-template-columns:repeat(3,1fr);gap:1px;padding:2px;border-radius:6px;border:2px solid var(--line);aspect-ratio:1}.scanprog .face.now{border-color:var(--ink)}.scanprog .face i{border-radius:2px;background:var(--line)}.scanbtns{display:flex;flex-wrap:wrap;gap:8px}@media(prefers-reduced-motion:reduce){.cam.flash:after{animation:none;opacity:0}}.cam .overlay{position:absolute;inset:0;width:100%;height:100%;pointer-events:none}.cam.mirror video{transform:scaleX(-1)}.cam{max-height:56dvh}.centres{display:grid;grid-template-columns:repeat(6,1fr);gap:6px}.centre{display:grid;justify-items:center;gap:4px;padding:8px 2px;border-radius:12px;border:2px solid transparent;font-size:.8rem;color:var(--muted)}.centre i{width:28px;height:28px;border-radius:8px;box-shadow:0 0 0 1px #0003 inset;position:relative}.centre.done{opacity:.45}.centre.done i:after{content:"";position:absolute;left:9px;top:4px;width:8px;height:15px;border:solid #1c2532;border-width:0 3px 3px 0;transform:rotate(45deg)}.centre.next{border-color:var(--mark);color:var(--ink);font-weight:700}@media(min-width:900px){#app:has(.screen.scan){max-width:920px}}