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var(--lesson-accent);background:var(--lesson-surface);margin-block:24px;padding:20px 23px}.lesson-shell .outcome>:first-child,.lesson-shell .example>:first-child,.lesson-shell .reflection>:first-child{margin-top:0}.lesson-shell .outcome>:last-child,.lesson-shell .example>:last-child,.lesson-shell .reflection>:last-child{margin-bottom:0}.lesson-shell .diagram{border:1px solid var(--lesson-line);border-radius:12px;margin-block:24px;padding:18px}.lesson-shell .diagram ol{grid-template-columns:repeat(auto-fit,minmax(min(100%,135px),1fr));gap:12px;margin:0;padding:0;list-style:none;display:grid}.lesson-shell .diagram li{border:1px solid var(--lesson-line);background:var(--lesson-surface);text-align:center;border-radius:8px;min-width:0;padding:10px 12px;font-size:.88rem;font-weight:650}.lesson-shell pre{border:1px solid var(--lesson-line);background:var(--lesson-surface);max-width:100%;color:var(--lesson-fg);tab-size:4;border-radius:10px;margin:20px 0;padding:18px;font:500 .84rem/1.65 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button{border:1px solid var(--lesson-accent);background:var(--lesson-accent);color:#fff;font:inherit;cursor:pointer;border-radius:7px;margin-top:12px;padding:9px 14px;font-size:.9rem;font-weight:700}.lesson-shell .quiz button:hover{filter:brightness(.9)}.lesson-shell .quiz-feedback{min-height:1.7em;margin:12px 0 0;font-weight:650}.lesson-shell .quiz-feedback[data-correct=true]{color:var(--lesson-accent)}.lesson-shell .quiz-feedback[data-correct=false]{color:#8b2e38}:root[data-theme=midnight] .lesson-shell .quiz button{color:#111a29}:root[data-theme=midnight] .lesson-shell .quiz-feedback[data-correct=false]{color:#ffafb4}.lesson-shell .source{border:1px solid var(--lesson-line);border-radius:10px;padding:16px 18px}.lesson-shell .lesson-nav{border-top:1px solid var(--lesson-line);flex-wrap:wrap;justify-content:space-between;gap:12px;margin-top:48px;padding-top:20px;font-size:.93rem;font-weight:700;display:flex}.lesson-shell .lesson-footer{color:var(--lesson-muted);padding-block:0 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