:root{--radius:14px;--tap:48px;--font:system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;--mono:ui-monospace, "SFMono-Regular", Menlo, Consolas, monospace;--ease:.18s ease;--rail:0px;--good:#1f8a4c;--good-bg:#e3f4ea;--bad:#c2362f;--bad-bg:#fbe7e5;--syn-tag:#b4235a;--syn-attr:#8a5a00;--syn-string:#1a7f37;--syn-comment:#5f6673;--lightningcss-light:initial;--lightningcss-dark: ;color-scheme:light}:root[data-mode=dark]{--good:#5fd08d;--good-bg:#183324;--bad:#ff8a80;--bad-bg:#3a1d1b;--syn-tag:#ff86b0;--syn-attr:#f0b35b;--syn-string:#72d892;--syn-comment:#8d95a3;--lightningcss-light: 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20px}.done-icon{background:var(--good-bg);width:72px;height:72px;color:var(--good);border-radius:50%;place-items:center;margin:0 auto 8px;font-size:2.2rem;font-weight:800;display:grid}.done-icon.pop{animation:.42s ease-out pop}@keyframes pop{0%{opacity:0;transform:scale(.4)}70%{transform:scale(1.12)}to{transform:scale(1)}}@media (prefers-reduced-motion:reduce){.done-icon.pop{animation:none}}:root[data-calm] .done-icon.pop{animation:none}.done-actions{gap:10px;max-width:360px;margin:18px auto 0;display:grid}.visually-hidden{clip:rect(0 0 0 0);white-space:nowrap;width:1px;height:1px;position:absolute;overflow:hidden}.pill-accent{background:var(--accent);color:var(--accent-ink);font-weight:700}.challenge-num{background:var(--accent);color:var(--accent-ink);font-size:1.1rem}.eyebrow{text-transform:uppercase;letter-spacing:.06em;color:var(--muted);margin:0 0 4px;font-size:.8rem;font-weight:700}.challenge h2{margin:0 0 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12px;font-size:.95rem}.clash-options{gap:10px;display:grid}.clash-option{border:2px solid var(--border);background:var(--surface);min-height:52px;color:var(--text);font:inherit;text-align:left;cursor:pointer;touch-action:manipulation;border-radius:12px;padding:10px 14px}.clash-option.mono{font-family:var(--mono)}.clash-option:active:not(:disabled){border-color:var(--brand)}.clash-option:disabled{cursor:default;color:var(--text)}.clash-option.correct{border-color:var(--good);background:var(--good-bg);font-weight:700}.clash-option.wrong{border-color:var(--bad);background:var(--bad-bg)}.clash-option.faded{opacity:.55}.clash-feedback{border-width:2px}.clash-feedback.good{border-color:var(--good)}.clash-feedback.bad{border-color:var(--bad)}.clash-verdict{margin:0 0 4px;font-size:1.15rem;font-weight:800}.clash-feedback.good .clash-verdict{color:var(--good)}.clash-feedback.bad .clash-verdict{color:var(--bad)}.clash-next{width:100%;margin-top:4px}.clash-final{color:var(--brand);margin:0;font-size:3rem;font-weight:800;line-height:1.1}.clash-best{margin:8px 0 0}.clash-best.new{color:var(--good);font-weight:800}.clash-outcome{margin:0 0 8px;font-size:1.5rem;font-weight:800}.clash-outcome.win{color:var(--good)}.clash-versus{justify-content:center;align-items:center;gap:16px;margin:4px 0;display:flex}.clash-versus>div{background:var(--code-bg);border-radius:12px;flex-direction:column;align-items:center;min-width:96px;padding:10px;display:flex}.clash-versus>div:first-child .stat-num{color:var(--brand)}.clash-share-note{text-align:left;color:var(--muted);margin:0}.clash-share-link{width:100%;min-height:var(--tap);border:1px solid var(--border);background:var(--code-bg);color:var(--text);font:.85rem var(--mono);border-radius:10px;margin-top:6px;padding:0 12px;display:block}.clash-review-title{margin:0 0 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0}.segmented{background:var(--code-bg);border-radius:10px;padding:3px;display:flex}.segmented button{min-height:40px;color:var(--muted);font:inherit;background:0 0;border:0;border-radius:8px;padding:0 12px;font-size:.875rem}.segmented button.on{background:var(--surface);color:var(--text);font-weight:600}.switch{appearance:none;background:var(--border);cursor:pointer;width:48px;height:28px;transition:background var(--ease);border-radius:999px;flex:none;position:relative}.switch:after{content:"";width:22px;height:22px;transition:transform var(--ease);background:#fff;border-radius:50%;position:absolute;top:3px;left:3px}.switch:checked{background:var(--brand)}.switch:checked:after{transform:translate(20px)}.options li.wrong{border-color:var(--bad);background:var(--bad-bg)}.xp-badge{background:var(--accent);color:var(--accent-ink);border-radius:999px;padding:2px 10px;font-size:.8rem;font-weight:700;display:inline-block}.palette-grid{grid-template-columns:repeat(3,1fr);gap:8px;margin-top:12px;display:grid}.palette-option{min-height:var(--tap);border:2px solid var(--border);background:var(--surface);color:var(--text);font:inherit;text-align:left;cursor:pointer;border-radius:10px;flex-direction:column;align-items:flex-start;gap:6px;padding:10px;font-size:.8rem;display:flex}.palette-option.on{border-color:var(--brand);font-weight:700}.swatches{gap:4px;display:flex}.swatches span{border:1px solid #0000001f;border-radius:50%;width:18px;height:18px}@media (width>=768px){:root{--rail:88px}.topbar{padding-left:calc(var(--rail) + 24px)}.tabbar{width:var(--rail);border-top:0;border-right:1px solid var(--border);flex-direction:column;justify-content:flex-start;gap:6px;padding:72px 8px 16px;top:0;bottom:0;right:auto}.tab{width:100%;min-width:0;padding:10px 0}.tab.active{background:var(--code-bg)}.screen{max-width:960px;padding:28px 32px 48px calc(var(--rail) + 32px)}h1{font-size:1.85rem}.lesson-list{grid-template-columns:repeat(2,1fr);gap:14px;display:grid}.lesson-list .card{height:100%;margin-bottom:0}.q-list{grid-template-columns:repeat(2,1fr);align-items:start;gap:14px;display:grid}.q-list .card{margin-bottom:0}.lesson,.clash,.settings-list{margin-inline:auto}.lesson{max-width:760px}.clash{max-width:720px}.live-wrap{margin:16px 0}.live-block{border:1px solid var(--border);border-radius:10px;overflow:hidden}.player-nav{grid-template-columns:160px 220px;justify-content:space-between;bottom:0}.player-nav.single{grid-template-columns:320px;justify-content:end}.settings-list{max-width:640px}a.card:hover{border-color:color-mix(in srgb, var(--brand) 35%, var(--border))}.clash-options{grid-template-columns:1fr 1fr}}@media (width>=1100px){:root{--rail:232px}.topbar{width:var(--rail);z-index:3;background:0 0;border-bottom:0;padding:16px 20px;position:fixed;top:0;left:0}.tabbar{padding:76px 12px 16px}.tab{flex-direction:row;justify-content:flex-start;gap:12px;padding:10px 14px;font-size:.95rem}.tab-icon{margin:0}.screen{max-width:calc(1120px + var(--rail));padding:40px 48px 64px calc(var(--rail) + 48px)}.lesson-list{grid-template-columns:repeat(3,1fr)}.lesson.challenge{max-width:1120px}.challenge-grid{grid-template-columns:minmax(0,1fr) 340px;align-items:start;gap:16px;display:grid}.challenge-side{max-height:calc(100dvh - 32px);position:sticky;top:16px;overflow-y:auto}.challenge-side .player-nav{background:0 0;grid-template-columns:1fr;padding:0;position:static}}:focus-visible{outline:3px solid var(--accent);outline-offset:2px}