:root{--cube-white: #fdfdfd;--cube-yellow: #ffd500;--cube-red: #c41e3a;--cube-orange: #ff5800;--cube-blue: #0051ba;--cube-green: #009e60;--ink: #0c0e12;--surface: #15181f;--surface-2: #1e222b;--ink-100: #f4f6fb;--ink-300: #c2c8d4;--ink-500: #8b93a3;--accent: var(--cube-green);--sans: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;--mono: ui-monospace, "SF Mono", "Cascadia Code", "JetBrains Mono", Menlo, Consolas, monospace}*,*:before,*:after{box-sizing:border-box}html,body{height:100%}body{margin:0;min-height:100%;font-family:var(--sans);color:var(--ink-100);background:radial-gradient(120% 90% at 50% -10%,#20242e 0%,var(--ink) 60%) fixed,var(--ink);-webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility;overflow:hidden}#app{position:fixed;inset:0}#app canvas{display:block;width:100%;height:100%;touch-action:none}.wordmark{position:fixed;top:max(18px,env(safe-area-inset-top));left:max(20px,env(safe-area-inset-left));display:flex;align-items:center;gap:10px;pointer-events:none;user-select:none;z-index:10}.wordmark__glyph{display:grid;grid-template-columns:repeat(2,1fr);grid-template-rows:repeat(2,1fr);gap:2px;width:26px;height:26px;padding:3px;border-radius:7px;background:var(--surface-2);box-shadow:0 1px #ffffff0f inset,0 6px 16px #00000073}.wordmark__glyph span{border-radius:2px}.wordmark__glyph span:nth-child(1){background:var(--cube-red)}.wordmark__glyph span:nth-child(2){background:var(--cube-blue)}.wordmark__glyph span:nth-child(3){background:var(--cube-yellow)}.wordmark__glyph span:nth-child(4){background:var(--cube-green)}.wordmark__text{font-weight:700;font-size:18px;letter-spacing:.2px;color:var(--ink-100)}.wordmark__text b{color:var(--accent);font-weight:700}.hint{position:fixed;bottom:max(16px,env(safe-area-inset-bottom));left:0;right:0;text-align:center;font-size:13px;color:var(--ink-500);pointer-events:none;user-select:none;z-index:10}.cube-stage{position:fixed;inset:0}.alg-picker{position:fixed;top:max(18px,env(safe-area-inset-top));right:max(20px,env(safe-area-inset-right));display:flex;flex-wrap:wrap;gap:8px;justify-content:flex-end;max-width:min(60vw,460px);z-index:11}.alg-chip{appearance:none;border:1px solid rgba(255,255,255,.1);background:var(--surface);color:var(--ink-300);font-family:var(--sans);font-size:12.5px;font-weight:600;padding:7px 12px;border-radius:999px;cursor:pointer;transition:background .15s,color .15s,border-color .15s}.alg-chip:hover{background:var(--surface-2);color:var(--ink-100)}.alg-chip[aria-pressed=true]{background:var(--accent);border-color:transparent;color:#06150d}.player{position:fixed;left:50%;transform:translate(-50%);bottom:max(18px,env(safe-area-inset-bottom));width:min(92vw,560px);display:flex;flex-direction:column;gap:12px;padding:14px 16px;border-radius:16px;background:#15181fd1;border:1px solid rgba(255,255,255,.08);backdrop-filter:blur(10px);box-shadow:0 12px 40px #00000080;z-index:12}.player__notation{display:flex;flex-wrap:wrap;gap:6px;align-items:center;min-height:26px}.player__tok{font-family:var(--mono);font-size:13px;font-weight:600;color:var(--ink-500);padding:3px 7px;border-radius:6px;background:#ffffff08;transition:color .12s,background .12s}.player__tok--done{color:var(--ink-300)}.player__tok--current{color:#06150d;background:var(--accent)}.player__row{display:flex;align-items:center;gap:10px}.btn{appearance:none;border:1px solid rgba(255,255,255,.1);background:var(--surface-2);color:var(--ink-100);font-family:var(--sans);font-size:14px;font-weight:600;min-width:40px;height:40px;padding:0 12px;border-radius:10px;cursor:pointer;display:inline-flex;align-items:center;justify-content:center;transition:background .15s,opacity .15s}.btn:hover{background:#262b36}.btn:disabled{opacity:.4;cursor:default}.btn--primary{background:var(--accent);border-color:transparent;color:#06150d}.btn--primary:hover{background:#00b46d}.scrub{flex:1;accent-color:var(--accent);height:22px;cursor:pointer}.player__readout{font-family:var(--mono);font-size:12.5px;color:var(--ink-300);min-width:86px;text-align:right;white-space:nowrap}.player__speed{appearance:none;border:1px solid rgba(255,255,255,.1);background:var(--surface-2);color:var(--ink-100);font-family:var(--sans);font-size:13px;height:40px;padding:0 8px;border-radius:10px;cursor:pointer}@media (max-width: 520px){.alg-picker{max-width:70vw}.player__readout{min-width:64px}}#app{overflow-x:hidden;overflow-y:auto}a{color:inherit}a.btn,a.topbar__link{text-decoration:none}.btn--play{min-width:56px;font-size:16px}.page{min-height:100%;width:100%}.page--scroll{max-width:1120px;margin:0 auto;padding:clamp(16px,3vw,32px) clamp(16px,4vw,40px) 64px}.brand{display:inline-flex;align-items:center;gap:12px;user-select:none}.brand__glyph{display:grid;grid-template-columns:repeat(2,1fr);grid-template-rows:repeat(2,1fr);gap:2px;padding:3px;border-radius:7px;background:var(--surface-2);box-shadow:0 1px #ffffff0f inset,0 6px 16px #00000073}.brand__tile{border-radius:2px}.brand__tile:nth-child(1){background:var(--cube-red)}.brand__tile:nth-child(2){background:var(--cube-blue)}.brand__tile:nth-child(3){background:var(--cube-yellow)}.brand__tile:nth-child(4){background:var(--cube-green)}.brand__text{font-weight:700;letter-spacing:.2px;color:var(--ink-100)}.brand__text b{color:var(--accent);font-weight:700}.brand--sm .brand__glyph{width:26px;height:26px}.brand--sm .brand__text{font-size:18px}.brand--lg .brand__glyph{width:44px;height:44px;gap:3px;border-radius:11px;padding:4px}.brand--lg .brand__text{font-size:26px}.topbar{display:flex;align-items:center;justify-content:space-between;gap:16px;margin-bottom:clamp(24px,5vw,48px)}.topbar__left{display:flex;align-items:center;gap:16px}.topbar__nav{display:flex;gap:18px}.topbar__link{color:var(--ink-300);font-weight:600;font-size:14px;padding:8px 10px;border-radius:8px;transition:color .15s,background .15s}.topbar__link:hover{color:var(--ink-100);background:var(--surface)}.hero{display:flex;flex-direction:column;align-items:flex-start;gap:18px;max-width:720px;margin-bottom:clamp(28px,5vw,52px)}.hero__kicker{font-size:12px;font-weight:700;letter-spacing:.1em;text-transform:uppercase;color:var(--accent)}.hero__title{font-size:clamp(30px,6vw,54px);line-height:1.05;letter-spacing:-.02em;margin:4px 0 0;font-weight:800}.hero__lede{font-size:clamp(15px,2.2vw,18px);line-height:1.55;color:var(--ink-300);margin:0}.cube-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(230px,1fr));gap:18px;margin-bottom:clamp(24px,4vw,40px)}.card{display:flex;flex-direction:column;gap:16px;padding:18px;border-radius:18px;background:var(--surface);border:1px solid rgba(255,255,255,.07);box-shadow:0 10px 30px #00000059;transition:transform .18s,border-color .18s}.card--ready:hover{transform:translateY(-3px);border-color:#009e608c}.card--soon{opacity:.62}.card__face{display:grid;gap:3px;width:86px;height:86px;padding:6px;border-radius:12px;background:#0a0c10;box-shadow:inset 0 2px 8px #0009}.card__sticker{border-radius:3px;box-shadow:inset 0 0 0 1px #00000059}.card__body{display:flex;flex-direction:column;gap:6px}.card__title{font-size:24px;font-weight:800;margin:0;letter-spacing:-.01em}.card__blurb{margin:0;font-size:14px;line-height:1.5;color:var(--ink-300)}.card__meta{margin:4px 0 0;font-family:var(--mono);font-size:12px;color:var(--ink-500)}.card__cta{align-self:flex-start;margin-top:10px;padding:0 20px}.card__soon-tag{align-self:flex-start;margin-top:10px;font-size:12px;font-weight:700;letter-spacing:.04em;text-transform:uppercase;color:var(--ink-500);padding:6px 12px;border-radius:999px;border:1px dashed rgba(255,255,255,.16)}.teaser-rail{display:flex;align-items:center;justify-content:space-between;gap:20px;flex-wrap:wrap;padding:20px 22px;border-radius:16px;background:linear-gradient(120deg,#009e601f,#0051ba1a);border:1px solid rgba(255,255,255,.08)}.teaser-rail__kicker{display:inline-block;font-size:11px;font-weight:700;letter-spacing:.08em;text-transform:uppercase;color:var(--accent);margin-bottom:6px}.teaser-rail__title{margin:0 0 6px;font-size:18px}.teaser-rail__blurb{margin:0;font-size:14px;color:var(--ink-300);max-width:520px}.home__footer{margin-top:36px;padding-top:20px;border-top:1px solid rgba(255,255,255,.06)}.home__footer-note{margin:0;font-size:13px;color:var(--ink-500)}.track{display:flex;flex-direction:column;height:100%}.track__header{display:flex;align-items:center;gap:18px;padding:14px clamp(14px,3vw,26px);border-bottom:1px solid rgba(255,255,255,.07);background:#0c0e1299}.track__head-left{display:flex;align-items:center;gap:16px}.track__back{color:var(--ink-300);font-weight:600;font-size:14px;text-decoration:none;padding:6px 10px;border-radius:8px}.track__back:hover{color:var(--ink-100);background:var(--surface)}.track__head-title{display:flex;align-items:center;gap:10px;flex:1;min-width:0}.track__title{font-size:clamp(15px,2.2vw,19px);font-weight:700;margin:0;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}.track__progress{font-family:var(--mono);font-size:12.5px;color:var(--ink-300);white-space:nowrap}.track__body{flex:1;min-height:0;display:grid;grid-template-columns:minmax(220px,280px) minmax(0,1fr) minmax(260px,340px)}.track__steps,.track__lesson{overflow-y:auto;padding:18px}.track__steps{border-right:1px solid rgba(255,255,255,.07)}.track__lesson{border-left:1px solid rgba(255,255,255,.07)}.track__steps-head,.stage-head__title{font-size:12px;font-weight:700;letter-spacing:.06em;text-transform:uppercase;color:var(--ink-500)}.track__steps-head{margin-bottom:14px}.stage-head{display:flex;align-items:center;gap:8px;margin:16px 0 8px}.step-item{width:100%;display:flex;align-items:center;gap:10px;text-align:left;padding:10px 12px;margin-bottom:4px;border-radius:10px;border:1px solid transparent;background:transparent;color:var(--ink-300);font-family:var(--sans);font-size:14px;font-weight:600;cursor:pointer;transition:background .14s,color .14s,border-color .14s}.step-item:hover{background:var(--surface);color:var(--ink-100)}.step-item--active{background:var(--surface-2);border-color:#009e6080;color:var(--ink-100)}.step-item__label{flex:1}.step-item__tick{display:inline-flex;align-items:center;justify-content:center;width:18px;height:18px;border-radius:999px;border:1.5px solid var(--ink-500);font-size:11px;font-weight:800;color:transparent;flex-shrink:0}.step-item__tick--done{background:var(--accent);border-color:transparent;color:#06150d}.track__stage{display:flex;flex-direction:column;min-height:0;padding:16px}.stage__cube{position:relative;flex:1;min-height:280px;border-radius:16px;overflow:hidden;background:radial-gradient(120% 90% at 50% 0%,#1a1e27 0%,var(--ink) 70%);border:1px solid rgba(255,255,255,.06)}.stage__cube canvas,.notation__cube canvas{position:absolute;inset:0;width:100%;height:100%}.stage__controls{display:flex;flex-direction:column;gap:10px;align-items:center;margin-top:14px}.transport{display:flex;gap:10px}.stage__scrub-row{display:flex;align-items:center;gap:12px;width:min(100%,460px)}.speed{appearance:none;border:1px solid rgba(255,255,255,.1);background:var(--surface-2);color:var(--ink-100);font-family:var(--sans);font-size:13px;height:40px;padding:0 10px;border-radius:10px;cursor:pointer}.stage__readout{font-family:var(--mono);font-size:12.5px;color:var(--ink-300)}.lesson__stage{font-size:12px;font-weight:700;letter-spacing:.06em;text-transform:uppercase;color:var(--ink-500);margin-bottom:8px}.lesson__stage--teaser{color:var(--cube-yellow)}.lesson__goal{font-size:24px;font-weight:800;letter-spacing:-.01em;margin:0 0 12px}.lesson__explain{font-size:14.5px;line-height:1.6;color:var(--ink-300);margin:0 0 18px}.lesson__label{font-size:11px;font-weight:700;letter-spacing:.07em;text-transform:uppercase;color:var(--ink-500);margin-bottom:8px}.lesson__alg{display:flex;flex-wrap:wrap;gap:6px;margin-bottom:18px}.move-chip{font-family:var(--mono);font-size:14px;font-weight:700;color:var(--ink-300);padding:5px 10px;border-radius:8px;background:var(--surface-2);border:1px solid rgba(255,255,255,.06);transition:color .12s,background .12s,border-color .12s}.move-chip--done{color:var(--ink-500)}.move-chip--current{color:#06150d;background:var(--accent);border-color:transparent}.lesson__notes{font-size:13px;line-height:1.55;color:var(--ink-500);padding:12px 14px;border-radius:12px;background:#ffffff08;border-left:3px solid rgba(255,255,255,.12);margin:0 0 18px}.lesson__nav{display:flex;gap:10px;justify-content:space-between}.lesson__nav .btn{flex:1}.cases{display:flex;gap:8px;overflow-x:auto;-webkit-overflow-scrolling:touch;padding-bottom:6px;margin-bottom:16px;scrollbar-width:thin}.case-chip{flex:0 0 auto;white-space:nowrap;appearance:none;font-family:var(--sans);font-size:13px;font-weight:600;color:var(--ink-300);background:var(--surface-2);border:1px solid rgba(255,255,255,.08);padding:8px 13px;border-radius:999px;cursor:pointer;transition:background .14s,color .14s,border-color .14s}.case-chip:hover{color:var(--ink-100);border-color:#009e6073}.case-chip--active{color:#06150d;background:var(--accent);border-color:transparent}.lesson__recognition{padding:12px 14px;border-radius:12px;background:#009e6014;border:1px solid rgba(0,158,96,.25);margin:0 0 18px}.lesson__recognition-kicker{font-size:11px;font-weight:700;letter-spacing:.06em;text-transform:uppercase;color:var(--accent);margin-bottom:6px}.lesson__recognition-text{margin:0;font-size:14px;line-height:1.55;color:var(--ink-100)}.btn:focus-visible,a.btn:focus-visible,.case-chip:focus-visible,.step-item:focus-visible,.move-btn:focus-visible,.speed:focus-visible,.scrub:focus-visible,.topbar__link:focus-visible,.track__back:focus-visible,.lesson__case:focus-visible{outline:2px solid var(--accent);outline-offset:2px}.pill{display:inline-flex;align-items:center;font-size:10.5px;font-weight:700;letter-spacing:.04em;text-transform:uppercase;padding:3px 8px;border-radius:999px}.pill--teaser{color:var(--cube-yellow);background:#ffd5001f;border:1px solid rgba(255,213,0,.3)}.pill--xs{font-size:9px;padding:2px 6px}.notfound{max-width:460px;margin:14vh auto 0;text-align:center;display:flex;flex-direction:column;align-items:center;gap:14px}.notfound__title{margin:0;font-size:26px}.notfound__body{margin:0;color:var(--ink-300)}.notation__intro{max-width:680px;margin-bottom:28px}.notation__title{font-size:clamp(26px,5vw,40px);letter-spacing:-.02em;margin:0 0 12px;font-weight:800}.notation__lede{font-size:16px;line-height:1.6;color:var(--ink-300);margin:0}.notation__cols{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1fr);gap:28px;align-items:start}.notation__demo{position:sticky;top:16px;display:flex;flex-direction:column;gap:14px}.notation__cube{position:relative;aspect-ratio:1 / 1;width:100%;border-radius:18px;overflow:hidden;background:radial-gradient(120% 90% at 50% 0%,#1a1e27 0%,var(--ink) 70%);border:1px solid rgba(255,255,255,.06)}.notation__moves{display:flex;flex-wrap:wrap;gap:8px}.move-btn{appearance:none;font-family:var(--mono);font-size:15px;font-weight:700;color:var(--ink-100);background:var(--surface-2);border:1px solid rgba(255,255,255,.1);min-width:48px;height:44px;padding:0 14px;border-radius:10px;cursor:pointer;transition:background .14s,border-color .14s}.move-btn:hover{background:#262b36;border-color:#009e6080}.notation__hint{font-size:13px;color:var(--ink-500);margin:0}.notation__h2{font-size:18px;margin:0 0 12px}.notation__legend>.notation__h2:not(:first-child){margin-top:26px}.notation__faces,.notation__mods{list-style:none;margin:0;padding:0;display:flex;flex-direction:column;gap:8px}.notation__face,.notation__mod{display:flex;align-items:center;gap:12px;font-size:14px;color:var(--ink-300)}.notation__key{font-family:var(--mono);font-size:14px;font-weight:700;color:var(--ink-100);background:var(--surface-2);border:1px solid rgba(255,255,255,.08);min-width:34px;text-align:center;padding:4px 8px;border-radius:7px}.notation__para{font-size:14px;line-height:1.6;color:var(--ink-300);margin:0}.notation__footer{margin-top:36px}.hero__cta-row{display:flex;align-items:center;gap:14px;flex-wrap:wrap;margin-top:4px}.hero__cta{padding:0 22px;height:46px}.hero__cta-note{font-size:13.5px;color:var(--ink-500);font-weight:600}.pg{display:flex;flex-direction:column;height:100%}.pg__header{display:flex;align-items:center;gap:18px;flex-wrap:wrap;padding:12px clamp(14px,3vw,26px);border-bottom:1px solid rgba(255,255,255,.07);background:#0c0e1299}.pg__head-left{display:flex;align-items:center;gap:16px}.pg__tablist{display:flex;gap:6px;padding:4px;border-radius:12px;background:var(--surface);border:1px solid rgba(255,255,255,.07)}.pg__tab{appearance:none;border:none;background:transparent;color:var(--ink-300);font-family:var(--sans);font-size:14px;font-weight:700;padding:8px 20px;border-radius:9px;cursor:pointer;transition:background .15s,color .15s}.pg__tab:hover{color:var(--ink-100)}.pg__tab--active{background:var(--accent);color:#06150d}.pg__panel{flex:1;min-height:0;overflow-y:auto;padding:clamp(14px,2.5vw,26px)}.pg-practice{display:grid;grid-template-columns:minmax(0,1fr) minmax(300px,380px);gap:clamp(16px,2.5vw,28px);max-width:1180px;margin:0 auto;align-items:start}.pg-practice__main{display:flex;flex-direction:column;gap:12px;min-width:0}.pg-cube{position:relative;width:100%;aspect-ratio:1 / 1;max-height:62vh;border-radius:16px;overflow:hidden;background:radial-gradient(120% 90% at 50% 0%,#1a1e27 0%,var(--ink) 70%);border:1px solid rgba(255,255,255,.06)}.pg-cube canvas{position:absolute;inset:0;width:100%;height:100%}.pg-cube__hint{margin:0;font-size:12.5px;color:var(--ink-500);text-align:center}.pg-scramble{display:flex;align-items:baseline;gap:10px;flex-wrap:wrap;padding:10px 14px;border-radius:12px;background:var(--surface);border:1px solid rgba(255,255,255,.06)}.pg-scramble__label{font-size:11px;font-weight:700;letter-spacing:.07em;text-transform:uppercase;color:var(--ink-500);flex-shrink:0}.pg-scramble__text{font-family:var(--mono);font-size:14px;color:var(--ink-100);line-height:1.5;word-break:break-word}.pg-practice__side{display:flex;flex-direction:column;gap:16px;min-width:0}.pg-size{display:inline-flex;gap:6px;padding:4px;border-radius:12px;background:var(--surface);border:1px solid rgba(255,255,255,.07);align-self:flex-start}.pg-size__btn{appearance:none;border:none;background:transparent;color:var(--ink-300);font-family:var(--mono);font-size:13px;font-weight:700;min-width:44px;height:36px;padding:0 10px;border-radius:9px;cursor:pointer;transition:background .14s,color .14s}.pg-size__btn:hover{color:var(--ink-100)}.pg-size__btn--active{background:var(--accent);color:#06150d}.pg-toolbar{display:flex;flex-wrap:wrap;gap:8px}.pg-toolbar__scramble{flex:1 0 auto}.pg-counter{display:flex;align-items:baseline;gap:8px}.pg-counter__label{font-size:11px;font-weight:700;letter-spacing:.07em;text-transform:uppercase;color:var(--ink-500)}.pg-counter__value{font-family:var(--mono);font-size:22px;font-weight:800;color:var(--ink-100)}.pg-moves__label{font-size:11px;font-weight:700;letter-spacing:.07em;text-transform:uppercase;color:var(--ink-500)}.pg-moves{display:flex;flex-direction:column;gap:8px}.pg-moves__row{display:flex;flex-wrap:wrap;gap:6px}.pg-move{min-width:44px;height:42px;font-size:14px;padding:0 10px}.pg-guide{border-radius:12px;background:#ffffff08;border:1px solid rgba(255,255,255,.07);padding:4px 14px}.pg-guide__summary{font-size:13.5px;font-weight:700;color:var(--ink-100);cursor:pointer;padding:10px 0;list-style:revert}.pg-guide__summary:focus-visible{outline:2px solid var(--accent);outline-offset:2px}.pg-guide__body{display:flex;flex-direction:column;gap:12px;padding:6px 0 14px}.pg-guide__tip{display:flex;flex-direction:column;gap:3px}.pg-guide__tag{font-size:11px;font-weight:700;letter-spacing:.04em;text-transform:uppercase;color:var(--accent)}.pg-guide__text{margin:0;font-size:13px;line-height:1.55;color:var(--ink-300)}.pg-guide__link{font-size:13.5px;font-weight:700;color:var(--accent);text-decoration:none}.pg-guide__link:hover{text-decoration:underline}.pg-celebrate{position:absolute;inset:0;display:flex;align-items:center;justify-content:center;pointer-events:none;overflow:hidden;z-index:5}.pg-celebrate__card{text-align:center;padding:18px 28px;border-radius:16px;background:#0c0e12c7;border:1px solid rgba(0,158,96,.5);box-shadow:0 12px 40px #00000080;backdrop-filter:blur(4px)}.pg-celebrate__title{font-size:28px;font-weight:800;color:var(--accent)}.pg-celebrate__sub{font-family:var(--mono);font-size:14px;color:var(--ink-300);margin-top:4px}.pg-confetti{position:absolute;top:-12px;width:9px;height:14px;border-radius:2px;opacity:.95;animation:pg-fall 1.8s linear forwards}@keyframes pg-fall{0%{transform:translateY(-10%) rotate(0);opacity:1}to{transform:translateY(115%) rotate(540deg);opacity:0}}@media (prefers-reduced-motion: reduce){.pg-confetti{display:none}}.pg-timer{display:flex;flex-direction:column;gap:16px;max-width:720px;margin:0 auto}.pg-timer__bar{display:flex;align-items:center;justify-content:space-between;gap:12px;flex-wrap:wrap}.pg-toggle{appearance:none;font-family:var(--sans);font-size:13px;font-weight:700;color:var(--ink-300);background:var(--surface-2);border:1px solid rgba(255,255,255,.1);height:38px;padding:0 16px;border-radius:999px;cursor:pointer;transition:background .14s,color .14s,border-color .14s}.pg-toggle:hover{color:var(--ink-100)}.pg-toggle--on{background:var(--accent);border-color:transparent;color:#06150d}.pg-scramble--timer{justify-content:center}.pg-scramble--timer .pg-scramble__text{font-size:clamp(14px,2vw,17px);text-align:center}.pg-pad{display:flex;flex-direction:column;align-items:center;justify-content:center;gap:8px;min-height:240px;border-radius:20px;background:var(--surface);border:2px solid rgba(255,255,255,.08);cursor:pointer;user-select:none;touch-action:none;transition:background .12s,border-color .12s}.pg-pad__time{font-family:var(--mono);font-size:clamp(48px,12vw,88px);font-weight:800;line-height:1;letter-spacing:-.02em;color:var(--ink-100);font-variant-numeric:tabular-nums}.pg-pad__hint{font-size:14px;font-weight:600;color:var(--ink-500)}.pg-pad--inspecting{background:#0051ba29;border-color:#0051ba99}.pg-pad--arming{background:#ffd5001f;border-color:#ffd50099}.pg-pad--arming .pg-pad__time{color:var(--cube-yellow)}.pg-pad--ready{background:#009e602e;border-color:var(--accent)}.pg-pad--ready .pg-pad__time{color:var(--accent)}.pg-pad--running{border-color:#ffffff2e}.pg-stats{display:grid;grid-template-columns:repeat(6,1fr);gap:8px}.pg-stat{display:flex;flex-direction:column;gap:4px;padding:12px 10px;border-radius:12px;background:var(--surface);border:1px solid rgba(255,255,255,.06);text-align:center}.pg-stat__label{font-size:10px;font-weight:700;letter-spacing:.06em;text-transform:uppercase;color:var(--ink-500)}.pg-stat__value{font-family:var(--mono);font-size:16px;font-weight:700;color:var(--ink-100);font-variant-numeric:tabular-nums}.pg-attempts__head{display:flex;align-items:center;justify-content:space-between;gap:12px}.pg-attempts__title{font-size:11px;font-weight:700;letter-spacing:.07em;text-transform:uppercase;color:var(--ink-500)}.pg-attempts__clear{height:34px;font-size:13px;padding:0 14px}.pg-attempts{list-style:none;margin:0;padding:0;display:flex;flex-direction:column;gap:6px}.pg-attempt{display:flex;align-items:center;gap:12px;padding:8px 12px;border-radius:10px;background:var(--surface);border:1px solid rgba(255,255,255,.05)}.pg-attempt__idx{font-family:var(--mono);font-size:12px;color:var(--ink-500);min-width:34px}.pg-attempt__time{font-family:var(--mono);font-size:16px;font-weight:700;color:var(--ink-100);flex:1;font-variant-numeric:tabular-nums}.pg-attempt__time--dnf{color:var(--cube-red)}.pg-attempt__actions{display:flex;gap:6px}.pg-attempt__btn{appearance:none;font-family:var(--sans);font-size:12px;font-weight:700;color:var(--ink-300);background:var(--surface-2);border:1px solid rgba(255,255,255,.08);min-width:38px;height:32px;padding:0 8px;border-radius:8px;cursor:pointer;transition:background .14s,color .14s,border-color .14s}.pg-attempt__btn:hover{color:var(--ink-100);border-color:#ffffff2e}.pg-attempt__btn--on{background:var(--cube-yellow);border-color:transparent;color:#1a1400}.pg-attempt__btn--del:hover{border-color:var(--cube-red);color:var(--cube-red)}.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}.pg__tab:focus-visible,.pg__panel:focus-visible,.pg-size__btn:focus-visible,.pg-move:focus-visible,.pg-toggle:focus-visible,.pg-pad:focus-visible,.pg-attempt__btn:focus-visible{outline:2px solid var(--accent);outline-offset:2px}@media (max-width: 920px){.track{height:auto;min-height:100%}.track__body{display:flex;flex-direction:column;flex:none;min-height:0;overflow:visible}.track__steps,.track__lesson{overflow-y:visible;border:none;border-top:1px solid rgba(255,255,255,.07)}.track__stage{order:1}.track__lesson{order:2}.track__steps{order:3}.stage__cube{flex:none;height:60vh;min-height:300px}.notation__cols{grid-template-columns:1fr}.notation__demo{position:static}.notation__cube{max-width:380px}.pg-practice{grid-template-columns:1fr}.pg-cube{aspect-ratio:auto;height:56vh;min-height:300px;max-height:none}}@media (max-width: 560px){.pg__header{gap:12px}.pg__tablist{width:100%;justify-content:center}.pg__tab{flex:1;text-align:center}.pg-stats{grid-template-columns:repeat(3,1fr)}.pg-pad{min-height:200px}.pg-attempt__time{font-size:15px}}@media (max-width: 920px){.pg-practice{grid-template-columns:1fr}.pg-cube{max-height:none}.pg-stats{grid-template-columns:repeat(3,1fr)}}@media (max-width: 540px){.pg__header{gap:10px}.pg__tab{padding:8px 16px}.pg-pad{min-height:190px}.pg-move{min-width:42px;height:44px}.pg-attempt{flex-wrap:wrap;gap:8px}.pg-attempt__time{flex:1 0 auto}}.update-banner{position:fixed;right:16px;bottom:16px;z-index:50;display:flex;align-items:center;gap:12px;max-width:min(360px,calc(100vw - 32px));padding:10px 12px;border-radius:12px;background:var(--surface-2);color:var(--ink-100);border:1px solid rgba(255,255,255,.08);box-shadow:0 12px 40px #00000080;font-size:13px;line-height:1.35}.update-banner__msg{flex:1 1 auto;color:var(--ink-300)}.update-banner__refresh{flex:0 0 auto;padding:7px 14px;border:none;border-radius:999px;background:var(--accent);color:var(--ink);font:inherit;font-weight:700;cursor:pointer}.update-banner__refresh:hover{filter:brightness(1.08)}.update-banner__dismiss{flex:0 0 auto;width:26px;height:26px;display:inline-flex;align-items:center;justify-content:center;padding:0;border:none;border-radius:999px;background:transparent;color:var(--ink-500);font-size:18px;line-height:1;cursor:pointer}.update-banner__dismiss:hover{color:var(--ink-100);background:#ffffff0f}.update-banner__refresh:focus-visible,.update-banner__dismiss:focus-visible{outline:2px solid var(--accent);outline-offset:2px}@media (max-width: 540px){.update-banner{left:12px;right:12px;bottom:12px;max-width:none}}