:root{color-scheme:light;--ink:#1d2433;--muted:#5d6678;--line:#dde3ee;--paper:#fbfcff;--panel:#fff;--blue:#2563eb;--green:#18a058;--yellow:#f5c542;--red:#d43f3a;--orange:#ef8f28;--shadow:0 18px 48px rgba(29,36,51,.08)}*{box-sizing:border-box}body{margin:0;color:var(--ink);background:linear-gradient(180deg,rgba(37,99,235,.07),rgba(255,255,255,0) 260px),var(--paper);font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;line-height:1.55}main{width:min(1040px,calc(100% - 32px));margin:0 auto;padding:32px 0 56px}.hero{display:grid;grid-template-columns:minmax(0,1.2fr) minmax(260px,.8fr);gap:32px;align-items:center;min-height:360px}.eyebrow{margin:0 0 10px;color:var(--blue);font-size:.82rem;font-weight:800;text-transform:uppercase}h1,h2,h3{margin:0;line-height:1.08;letter-spacing:0}h1{max-width:780px;font-size:clamp(2.1rem,7vw,4.5rem)}h2{margin-top:42px;font-size:clamp(1.45rem,3vw,2.15rem)}h3{margin-top:0;font-size:1.08rem}p{margin:12px 0 0}.lead{max-width:640px;color:var(--muted);font-size:1.12rem}.lesson-meta{display:flex;flex-wrap:wrap;gap:10px;margin-top:22px}.pill{border:1px solid var(--line);border-radius:999px;background:#fff;padding:7px 11px;color:var(--muted);font-size:.9rem;font-weight:650}.cube-wrap{display:grid;place-items:center}.cube{display:grid;grid-template-columns:repeat(3,58px);gap:7px;transform:rotate(-7deg);padding:16px;background:#1a1f2b;border-radius:8px;box-shadow:var(--shadow)}.sticker{width:58px;aspect-ratio:1;border-radius:6px;border:2px solid rgba(0,0,0,.15)}.w{background:#f8fafc}.y{background:var(--yellow)}.r{background:var(--red)}.o{background:var(--orange)}.g{background:var(--green)}.b{background:var(--blue)}.grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:14px;margin-top:18px}.card,.task,.quiz{border:1px solid var(--line);border-radius:8px;background:var(--panel);padding:18px;box-shadow:0 8px 26px rgba(29,36,51,.045)}.card strong{display:block;margin-bottom:4px}.turns{display:grid;grid-template-columns:repeat(6,minmax(88px,1fr));gap:10px;margin-top:18px}.turn{border:1px solid var(--line);border-radius:8px;background:#fff;padding:14px 10px;text-align:center}.turn code{display:block;font-size:1.45rem;font-weight:850}code{border-radius:6px;background:#eef3ff;padding:.1em .32em;color:#183b8f}.steps{display:grid;gap:12px;margin-top:18px;padding:0;list-style:none}.steps li{display:grid;grid-template-columns:36px 1fr;gap:12px;align-items:start;border:1px solid var(--line);border-radius:8px;background:#fff;padding:14px}.num{display:grid;place-items:center;width:32px;aspect-ratio:1;border-radius:8px;background:var(--ink);color:#fff;font-weight:800}.task{margin-top:18px;background:#fffdf4}.task label{display:flex;gap:10px;align-items:flex-start;margin-top:12px;color:var(--ink);font-weight:650}.quiz{margin-top:18px}.choices{display:grid;gap:10px;margin-top:14px}button{min-height:44px;border:1px solid var(--line);border-radius:8px;background:#fff;color:var(--ink);font:inherit;font-weight:750;cursor:pointer}button:hover,button:focus-visible{border-color:var(--blue);outline:none}.feedback{min-height:28px;margin-top:12px;font-weight:750}.source{color:var(--muted);font-size:.95rem}a{color:#174ea6;font-weight:700}@media (max-width:760px){main{width:min(100% - 24px,640px);padding-top:22px}.hero,.grid{grid-template-columns:1fr}.cube{grid-template-columns:repeat(3,46px)}.sticker{width:46px}.turns{grid-template-columns:repeat(2,minmax(0,1fr))}}