:root{color-scheme:dark;--bg:#10131b;--panel:#191e2a;--line:#303747;--text:#eff2fa;--muted:#a4adc2;--lime:#d7ff72;--violet:#b5a0ff;--good:#a8edcb;--bad:#ffb7b7;font-family:Inter,ui-sans-serif,system-ui,sans-serif}*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:30px}body{margin:0;background:var(--bg);color:var(--text)}a{color:inherit;text-decoration:none}button,input{font:inherit}button,.button{border:1px solid var(--line);border-radius:9px;padding:12px 18px;color:var(--text);background:#232a39;cursor:pointer;display:inline-block;font-weight:650}button:hover,.button:hover{border-color:var(--lime)}button:disabled{opacity:.55;cursor:default}.primary{background:var(--lime);border-color:var(--lime);color:#152008}.subtle{background:transparent;border:0;padding:8px}header{max-width:1360px;padding:25px 36px;margin:auto;display:flex;align-items:center;justify-content:space-between;border-bottom:1px solid 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h3{font-size:39px;letter-spacing:-1px}.pricing small{font-size:12px;color:var(--muted)}.pricing li{font-size:13px;color:var(--muted);line-height:1.9}.pricing ul{padding-left:18px;min-height:115px}.pricing .plan-button{width:100%;margin-top:18px}.featured{border-color:var(--lime)}.play{border:1px solid var(--violet);border-radius:16px;padding:30px;background:var(--panel);scroll-margin-top:24px}.play-top{display:flex;justify-content:space-between}.clock{font-size:24px;font-variant-numeric:tabular-nums;color:var(--lime)}.play h2{font-size:27px;line-height:1.5;margin:28px 0;white-space:pre-wrap}.choices{display:grid;grid-template-columns:1fr 1fr;gap:12px;margin:20px 0}.choice{text-align:left;font-size:21px;padding:20px}.choice span{display:inline-flex;align-items:center;justify-content:center;width:28px;height:28px;margin-right:16px;border:1px solid var(--line);font-size:12px;border-radius:5px}.choice.correct{border-color:var(--good);background:#254638}.choice.wrong{border-color:var(--bad);background:#4a2a35}.recognize{background:transparent;border-color:var(--violet);color:var(--violet)}.lesson{border-top:1px solid var(--line);padding-top:22px;color:var(--muted);font-size:14px;line-height:1.7}.lesson b{color:var(--text)}#feedback>p{line-height:1.8}#notice:not(:empty){padding:15px;border:1px solid var(--violet);border-radius:9px;color:var(--text);margin:15px 0}#scoreboard{padding:0;list-style:none}#scoreboard li{padding:13px 0;border-bottom:1px solid var(--line);display:flex;justify-content:space-between}footer{border-top:1px solid var(--line);display:flex;justify-content:space-between;gap:30px;padding:35px 0;color:var(--muted);font-size:12px}footer b{color:var(--text);letter-spacing:2px;font-size:11px}[hidden]{display:none!important}:focus-visible{outline:3px solid var(--violet);outline-offset:4px}@media(max-width:850px){header{padding:20px;align-items:flex-start}nav{flex-wrap:wrap;gap:10px}.brand .badge{display:none}.hero{gap:25px;padding:45px 0;grid-template-columns:1fr}.hero-card{transform:none}.cards{grid-template-columns:1fr 1fr}.pricing{grid-template-columns:1fr}.pricing ul{min-height:0}.race-layout{grid-template-columns:1fr}}@media(max-width:500px){main{padding:0 18px}header{flex-direction:column}.cards,.choices{grid-template-columns:1fr}.metrics{gap:25px}.section-title{align-items:start;flex-direction:column}.play{padding:20px}.hero-card{padding:24px}h1{letter-spacing:-1.6px}footer{flex-direction:column}.intro{font-size:15px}}
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