:root{--ink:#1b2a4a;--ink-soft:#3a4a6b;--sky-bg:#eaf6ff;--sky:#4fc3f7;--sun:#ffc83d;--mint:#3dd68c;--coral:#ff8a65;--tomato:#ff6b4a;--grape-soft:#b39dff;--grape:#5b3fd9;--line-off:#c9d8ea;--white:#fff;--tint-sun:#fff3cf;--tint-sky:#e0f4fd;--tint-mint:#ddf8ea;--tint-coral:#ffe6dd;--tint-grape:#eee9ff;--navy-shadow:#0e1830;--ticket-soft:#b9c6e0;--ticket-line:#3f527a;--sun-shadow:#c8901a;--font-display:"Baloo 2", "Nunito", system-ui, sans-serif;--font-body:"Nunito", system-ui, sans-serif;--border:3px solid var(--ink);--shadow:0 6px 0 var(--ink);--shadow-small:0 4px 0 var(--ink);--radius-card:28px;--radius-tile:22px;font-family:var(--font-body);color:var(--ink);font-weight:600}*{box-sizing:border-box}body{background:var(--sky-bg);min-height:100vh;color:var(--ink);-webkit-font-smoothing:antialiased;-webkit-tap-highlight-color:transparent;margin:0}button,input{font:inherit;color:inherit}button{cursor:pointer;background:0 0;border:none}button:disabled{cursor:default}:focus-visible{outline:4px solid var(--grape);outline-offset:3px}.visually-hidden{clip:rect(0 0 0 0);white-space:nowrap;border:0;width:1px;height:1px;margin:-1px;padding:0;position:absolute;overflow:hidden}h1,h2,h3{font-family:var(--font-display);font-weight:800}.app{padding-bottom:64px}.app:not(.is-setup){max-width:900px;margin:0 auto;padding:20px 16px 48px}@media (width>=600px){.app:not(.is-setup){padding-inline:24px}}.screen{animation:.28s ease-out rise}@keyframes rise{0%{opacity:0;transform:translateY(12px)}to{opacity:1;transform:none}}.pill-btn{background:var(--white);border:var(--border);min-height:48px;box-shadow:var(--shadow-small);white-space:nowrap;border-radius:999px;justify-content:center;align-items:center;gap:8px;padding:0 18px;font-size:16px;font-weight:800;transition:transform 80ms,box-shadow 80ms;display:inline-flex}.pill-btn.is-sun{background:var(--sun)}.pill-btn.is-large{min-height:52px;box-shadow:0 5px 0 var(--ink);padding:0 24px;font-size:18px}.pill-btn.is-xl{min-height:60px;font-family:var(--font-display);box-shadow:var(--shadow);padding:0 32px;font-size:24px}.pill-btn:not(:disabled):active,.choice:not(:disabled):active,.number-key:active,.shortcut:active,.answer-btn:not(:disabled):active{box-shadow:0 1px 0 var(--ink);transform:translateY(3px)}.sound-btn.is-compact{width:48px;padding:0}.pill{white-space:nowrap;border-radius:999px;align-items:center;gap:6px;min-height:48px;padding:0 18px;font-size:16px;font-weight:800;display:inline-flex}.pill.is-navy{background:var(--ink);color:var(--white)}.pill.is-mint{background:var(--mint);border:var(--border)}.shortcut{border:2px solid var(--ink);background:var(--sky-bg);border-radius:999px;min-height:44px;padding:0 18px;font-size:15px;font-weight:800}.shortcut.is-easy{background:var(--tint-mint)}.shortcut.is-tricky{background:var(--tint-coral)}.shortcut.is-clear{background:var(--white);border-style:dashed;border-color:var(--ink-soft)}.sky-band{background:var(--sky);border-bottom:6px solid var(--ink);padding:20px 16px 0;overflow:hidden}@media (width>=600px){.sky-band{padding-inline:24px}}.band-inner{flex-direction:column;gap:16px;max-width:1160px;margin:0 auto;display:flex}.band-top{flex-wrap:wrap;justify-content:space-between;align-items:center;gap:12px;display:flex}.brand{align-items:center;gap:10px;display:flex}.logo-tile{background:var(--sun);border:var(--border);width:48px;height:48px;font-family:var(--font-display);border-radius:14px;place-items:center;font-size:30px;font-weight:800;line-height:1;display:grid}.brand-name{font-family:var(--font-display);font-size:20px;font-weight:800}.hero{flex-wrap:wrap;justify-content:space-between;align-items:flex-end;gap:24px;padding-top:12px;display:flex}.hero-copy{flex-direction:column;flex:420px;gap:14px;padding-bottom:28px;display:flex}.hero h1{letter-spacing:-.5px;margin:0;font-size:clamp(44px,7vw,84px);line-height:.95}.hero-sub{max-width:30ch;margin:0;font-size:22px;font-weight:700}.hero-actions{flex-wrap:wrap;gap:12px;display:flex}.hero-art{flex-direction:column;flex:0 380px;align-items:center;display:flex}.hero-car{max-width:100%;height:auto}.road{background:var(--ink);border-radius:12px 12px 0 0;justify-content:space-around;align-items:center;width:100%;height:40px;padding:0 12px;display:flex}.road span{background:var(--sun);border-radius:3px;width:36px;height:6px}@media (width<=480px){.hero-copy{flex-basis:100%;padding-bottom:8px}.hero-actions .pill-btn{flex:100%}.hero-sub{font-size:19px}}.garage{flex-wrap:wrap;align-items:flex-start;gap:28px;max-width:1160px;margin:0 auto;padding:32px 16px 0;scroll-margin-top:16px;display:flex}@media (width>=600px){.garage{padding:40px 24px 0}}.steps{flex-direction:column;flex:999 560px;gap:24px;min-width:0;display:flex}.step-card{background:var(--white);border:var(--border);border-radius:var(--radius-card);box-shadow:var(--shadow);flex-direction:column;gap:18px;padding:24px;display:flex}@media (width<=480px){.step-card{padding:18px 16px}}.step-head{align-items:center;gap:12px;display:flex}.step-num{background:var(--ink);width:44px;height:44px;color:var(--white);font-family:var(--font-display);border-radius:50%;flex:none;place-items:center;font-size:24px;font-weight:800;display:grid}.step-card h2{margin:0;font-size:30px;line-height:1.1}@media (width<=480px){.step-card h2{font-size:26px}}.step-hint{color:var(--ink-soft);margin:2px 0 0;font-size:16px;font-weight:700}.choice{--fill:var(--tint-sun);border-radius:var(--radius-tile);background:var(--white);border:3px solid var(--line-off);box-shadow:0 4px 0 var(--line-off);color:var(--ink);transition:transform 80ms,box-shadow 80ms,background .12s;position:relative}.choice:not(.is-on):hover{border-color:var(--ink-soft)}.choice.is-on{background:var(--fill);border-color:var(--ink);box-shadow:var(--shadow)}.check-badge{background:var(--ink);border-radius:50%;place-items:center;width:32px;height:32px;display:grid;position:absolute;top:12px;right:12px}.choice-name{font-family:var(--font-display);font-size:22px;font-weight:800;line-height:1.1}.choice-name.is-small{font-family:var(--font-body);font-size:17px}.choice-desc{color:var(--ink-soft);font-size:15px;font-weight:700;line-height:1.3}.race-grid{grid-template-columns:repeat(auto-fit,minmax(min(160px,100%),1fr));gap:14px;display:grid}@media (width<=480px){.race-grid{grid-template-columns:repeat(2,minmax(0,1fr))}}.race-tile{text-align:left;flex-direction:column;gap:8px;min-height:150px;padding:16px;display:flex}.race-symbol{border:var(--border);width:56px;height:56px;font-family:var(--font-display);border-radius:16px;place-items:center;font-size:34px;font-weight:800;line-height:1;display:grid}.number-row{flex-wrap:wrap;gap:10px;display:flex}.number-key{background:var(--white);border:3px solid var(--line-off);width:60px;height:60px;box-shadow:0 4px 0 var(--line-off);font-family:var(--font-display);border-radius:50%;font-size:26px;font-weight:800;line-height:1;transition:transform 80ms,box-shadow 80ms}.number-row.is-squares .number-key{font-size:21px}.number-key.is-on{background:var(--sun);border-color:var(--ink);box-shadow:var(--shadow)}@media (width<=400px){.number-row{gap:8px}.number-key{width:52px;height:52px;font-size:23px}.number-row.is-squares 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var(--ink);border-radius:7px;width:22px;height:22px}.type-box{background:var(--white);border:var(--border);width:52px;height:52px;font-family:var(--font-display);border-radius:12px;flex:none;justify-content:center;align-items:center;font-size:24px;font-weight:800;display:flex}.type-caret{background:var(--grape);width:3px;height:26px;margin-left:2px}.speed-block{flex-direction:column;gap:12px;padding-top:4px;display:flex}.speed-label{margin:0;font-size:17px;font-weight:800}.speed-grid{grid-template-columns:repeat(auto-fit,minmax(min(120px,100%),1fr));gap:12px;display:grid}@media (width<=480px){.speed-grid{grid-template-columns:repeat(2,minmax(0,1fr))}}.speed-tile{border-radius:20px;flex-direction:column;align-items:center;gap:6px;padding:14px 10px;display:flex}.speed-tile .check-badge{width:26px;height:26px;top:8px;right:8px}.speed-tile .check-badge svg{width:15px;height:15px}.speed-secs{font-family:var(--font-display);font-size:28px;font-weight:800;line-height:1}.speed-name{text-transform:uppercase;letter-spacing:1px;font-size:14px;font-weight:800}.count-row{flex-wrap:wrap;gap:14px;display:flex}.count-circle{border-radius:50%;flex-direction:column;justify-content:center;align-items:center;width:96px;height:96px;display:flex}.count-circle .check-badge{width:30px;height:30px;top:-6px;right:-6px}.count-value{font-family:var(--font-display);font-size:36px;font-weight:800;line-height:1}.count-label{font-size:13px;font-weight:800}@media (width<=400px){.count-row{gap:8px}.count-circle{width:68px;height:68px}.count-value{font-size:26px}.count-label{font-size:12px}}.ticket{background:var(--ink);min-width:0;color:var(--white);border-radius:var(--radius-card);box-shadow:0 8px 0 var(--navy-shadow);flex-direction:column;flex:320px;gap:18px;padding:24px;display:flex;position:sticky;top:24px}.ticket-head{justify-content:space-between;align-items:center;gap:12px;display:flex}.ticket h2{color:var(--sun);margin:0;font-size:28px}.ticket-sentence{margin:0;font-size:19px;font-weight:700;line-height:1.45}.ticket-rows{border-top:2px dashed var(--ticket-line);flex-direction:column;margin:0;display:flex}.ticket-rows div{border-bottom:2px dashed var(--ticket-line);justify-content:space-between;gap:12px;padding:10px 0;display:flex}.ticket-rows dt{color:var(--ticket-soft);font-size:15px;font-weight:700}.ticket-rows dd{text-align:right;margin:0;font-size:15px;font-weight:800}.ticket-warning{background:var(--tint-coral);color:var(--ink);border-radius:14px;margin:0;padding:12px 14px;font-size:15px;font-weight:800}.start-btn{border-radius:var(--radius-tile);background:var(--sun);border:3px solid var(--white);min-height:72px;box-shadow:0 6px 0 var(--sun-shadow);font-family:var(--font-display);letter-spacing:1px;color:var(--ink);justify-content:center;align-items:center;gap:12px;font-size:30px;font-weight:800;transition:transform 80ms,box-shadow 80ms;display:flex}.start-btn:not(:disabled):active{box-shadow:0 2px 0 var(--sun-shadow);transform:translateY(4px)}.start-btn:disabled{background:var(--ticket-line);border-color:var(--ticket-soft);box-shadow:none;color:var(--ticket-soft)}.start-btn:disabled svg path{fill:var(--ticket-soft)}.ticket-foot{color:var(--ticket-soft);text-align:center;margin:0;font-size:14px;font-weight:700}.ticket-records h3{color:var(--sun);margin:6px 0 8px;font-size:20px}.race{flex-direction:column;gap:22px;display:flex}.race-top{flex-wrap:wrap;justify-content:space-between;align-items:center;gap:12px;display:flex}.race-pills{flex-wrap:wrap;gap:10px;display:flex}@media (width<=480px){.race-top .pill,.race-top .pill-btn{min-height:44px;padding:0 14px;font-size:15px}.race-top 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18px;display:flex}.clock-row{align-items:center;gap:12px;width:100%;display:flex}.time-bar{background:var(--sky-bg);border:var(--border);border-radius:999px;flex:1;height:20px;overflow:hidden}.time-fill{background:var(--mint);height:100%;transition:width .1s linear,background .2s}.time-fill.is-low{background:var(--tomato)}.time-left{text-align:right;min-width:44px;font-family:var(--font-display);font-variant-numeric:tabular-nums;font-size:26px;font-weight:800}.stopwatch-time{font-family:var(--font-display);font-variant-numeric:tabular-nums;font-size:30px;font-weight:800}.stopwatch-label{color:var(--ink-soft);margin-left:auto;font-size:15px;font-weight:800}.equation{font-family:var(--font-display);font-variant-numeric:tabular-nums;flex-wrap:wrap;justify-content:center;align-items:center;gap:.18em;margin:0;font-size:clamp(48px,12vw,120px);font-weight:800;line-height:1.05;display:flex}.equation .op{padding:0 .04em}.slot{background:var(--tint-sun);border:4px dashed var(--ink);text-align:center;border-radius:20px;min-width:1.2em;padding:0 .12em;line-height:1.1;display:inline-block}.slot.is-good{background:var(--tint-mint)}.slot.is-bad{background:var(--tint-coral);animation:.35s shake}.feedback-area{place-items:center;min-height:52px;display:grid}.feedback{border:var(--border);font-family:var(--font-display);text-align:center;border-radius:999px;margin:0;padding:8px 20px;font-size:24px;font-weight:800;animation:.22s ease-out pop}.feedback.is-good{background:var(--mint)}.feedback.is-bad{background:var(--sun)}.answers{grid-template-columns:repeat(2,minmax(0,1fr));gap:16px;display:grid}.answer-btn{--fill:var(--tint-sun);border-radius:var(--radius-card);background:var(--fill);border:4px solid var(--ink);min-height:120px;box-shadow:0 7px 0 var(--ink);font-family:var(--font-display);font-variant-numeric:tabular-nums;font-size:56px;font-weight:800;line-height:1;transition:transform 80ms,box-shadow 80ms,opacity .2s,background 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40px;font-size:26px;font-weight:800}@keyframes pop{40%{transform:scale(1.04)}}@keyframes shake{25%{transform:translate(-7px)}75%{transform:translate(7px)}}.results{flex-direction:column;gap:22px;display:flex}.finish-card{background:var(--white);border:var(--border);box-shadow:0 8px 0 var(--ink);text-align:center;border-radius:32px;flex-direction:column;align-items:center;gap:18px;padding:36px 20px;display:flex}.stars{gap:10px;display:flex}.finish-title{margin:0;font-size:clamp(40px,9vw,56px);line-height:1}.finish-score{margin:0;font-size:22px;font-weight:800}.finish-actions{flex-wrap:wrap;justify-content:center;gap:12px;display:flex}.badge-row{flex-wrap:wrap;justify-content:center;gap:8px;display:flex}.badge{background:var(--tint-grape);border:2px solid var(--ink);border-radius:999px;padding:8px 16px;font-size:15px;font-weight:800}.stat-grid{grid-template-columns:repeat(auto-fit,minmax(150px,1fr));gap:12px;display:grid}.stat-card{background:var(--white);border:3px solid var(--line-off);border-radius:var(--radius-tile);padding:14px 16px}.stat-card.is-headline{background:var(--tint-sun);border-color:var(--ink)}.stat-label{color:var(--ink-soft);font-size:14px;font-weight:800;display:block}.stat-value{font-family:var(--font-display);font-variant-numeric:tabular-nums;margin-top:2px;font-size:32px;font-weight:800;line-height:1.1;display:block}.results-note{background:var(--tint-coral);border:2px solid var(--ink);border-radius:16px;margin:0;padding:12px 16px;font-weight:700;line-height:1.4}.panel{background:var(--white);border:var(--border);border-radius:var(--radius-card);box-shadow:var(--shadow);padding:22px}.panel h2{margin:0 0 12px;font-size:26px;line-height:1.15}.panel-hint{color:var(--ink-soft);margin:0 0 12px;font-weight:700}.practice-list{flex-wrap:wrap;gap:10px;margin:0;padding:0;list-style:none;display:flex}.practice-list li{background:var(--sky-bg);border:2px solid var(--ink);font-family:var(--font-display);font-variant-numeric:tabular-nums;border-radius:14px;align-items:baseline;gap:8px;padding:8px 14px;font-size:22px;font-weight:800;display:inline-flex}.practice-answer{background:var(--tint-coral);border-radius:10px;padding:0 8px}.learn{flex-direction:column;gap:20px;display:flex}.learn-head{flex-wrap:wrap;align-items:center;gap:16px;display:flex}.learn-title{margin:0;font-size:clamp(32px,6vw,44px);line-height:1}.tabs{grid-template-columns:repeat(auto-fit,minmax(110px,1fr));gap:8px;display:grid}.tab{background:var(--white);border:3px solid var(--line-off);min-height:48px;box-shadow:0 4px 0 var(--line-off);border-radius:999px;padding:0 10px;font-size:16px;font-weight:800}.tab.is-on{background:var(--sun);border-color:var(--ink);box-shadow:var(--shadow-small)}.learn .panel h2{margin-bottom:14px}.table-grid{flex-wrap:wrap;gap:10px;display:flex}.table-key{background:var(--white);border:3px solid var(--line-off);min-width:52px;height:52px;box-shadow:0 4px 0 var(--line-off);font-family:var(--font-display);border-radius:999px;padding:0 8px;font-size:22px;font-weight:800}.table-key.is-on{background:var(--sun);border-color:var(--ink);box-shadow:var(--shadow-small)}.fact-list{grid-template-columns:repeat(auto-fit,minmax(150px,1fr));gap:10px;margin:0;padding:0;list-style:none;display:grid}.fact-row{background:var(--white);border:3px solid var(--line-off);width:100%;min-height:48px;font-family:var(--font-display);font-variant-numeric:tabular-nums;border-radius:16px;justify-content:space-between;align-items:center;gap:10px;padding:8px 14px;font-size:19px;font-weight:700;display:flex}.fact-left{color:var(--ink-soft)}.fact-equals{display:none}.fact-answer{font-size:22px;font-weight:800}.fact-row.is-on{background:var(--tint-sky);border-color:var(--ink)}.array-model{justify-content:start;gap:6px;padding:4px 0;display:grid}.dot-row{gap:6px;display:flex}.visual-caption{color:var(--ink-soft);margin:0 0 12px;font-weight:700}.visual-caption strong{color:var(--ink)}.dot-flow{flex-wrap:wrap;gap:6px;max-width:420px;padding:4px 0;display:flex}.dot{background:var(--sky);border:2px solid var(--ink);border-radius:50%;flex:none}.dot.is-added{background:var(--mint)}.dot.is-gone{background:var(--white);border:2px dashed var(--ink-soft);position:relative}.dot.is-gone:after{content:"";border-top:3px solid var(--tomato);position:absolute;inset:45% -3px;transform:rotate(-45deg)}.array-empty{color:var(--ink-soft);padding:10px 0;font-weight:700}.array-empty strong{color:var(--ink);font-size:1.15rem}.chart-scroll{margin-top:14px;overflow-x:auto}.chart{border-collapse:collapse;font-variant-numeric:tabular-nums;width:100%;min-width:520px;font-size:.9rem}.chart th,.chart td{border:1px solid var(--line-off);text-align:center;color:var(--ink-soft);padding:6px 4px}.chart th{background:var(--sky-bg);color:var(--ink);font-weight:800}.chart th.is-axis{background:var(--sun)}.chart td.is-lit{background:var(--tint-sun);color:var(--ink);font-weight:800}.chart td.is-diagonal{outline:2px solid var(--grape);outline-offset:-2px}.chart-key{color:var(--ink-soft);margin:10px 0 0;font-size:.9rem;font-weight:700}.square-grid{grid-template-columns:repeat(auto-fit,minmax(94px,1fr));gap:10px;margin:0;padding:0;list-style:none;display:grid}.square-card{background:var(--white);border:3px solid var(--line-off);font-variant-numeric:tabular-nums;border-radius:16px;gap:2px;width:100%;padding:10px 12px;display:grid}.square-label{color:var(--ink-soft);font-size:15px;font-weight:800}.square-value{font-family:var(--font-display);font-size:26px;font-weight:800;line-height:1.1}.square-card.is-on{background:var(--tint-grape);border-color:var(--ink)}.learn-go{white-space:normal;text-align:center;align-self:center;max-width:100%;padding-block:10px}@media (prefers-reduced-motion:reduce){*,:before,:after{scroll-behavior:auto!important;transition:none!important;animation:none!important}}