:root{color-scheme:light;--bg:#f6f4ee;--panel:#fffdf8;--ink:#1e2528;--muted:#5d676b;--line:#d8d1c3;--teal:#177e75;--rust:#a54725;--gold:#b38719;--green:#49743a;--code-bg:#ebe7dc;font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,sans-serif;line-height:1.55}*{box-sizing:border-box}html{background:var(--bg)}body{color:var(--ink);margin:0}a{color:var(--teal);text-underline-offset:.16em;text-decoration-thickness:.08em}.lesson-header,.index-page{max-width:1240px;margin:0 auto;padding:40px 28px 18px}.eyebrow,.lesson-number{color:var(--rust);letter-spacing:0;text-transform:uppercase;margin:0 0 8px;font-size:.78rem;font-weight:800}h1,h2,h3,h4{letter-spacing:0;line-height:1.16}h1{max-width:900px;margin:0;font-size:clamp(2.35rem,7vw,5.6rem)}.dek{color:var(--muted);max-width:760px;margin:16px 0 0;font-size:clamp(1.05rem,2vw,1.35rem)}.lesson-meta{flex-wrap:wrap;gap:10px;margin:28px 0 0;display:flex}.lesson-meta div,.status-pill{background:var(--panel);border:1px 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18px;font-size:1.08rem;font-weight:700}.lesson-content table{border-collapse:collapse;width:100%;margin:22px 0 28px;display:block;overflow-x:auto}.lesson-content th,.lesson-content td{border:1px solid var(--line);text-align:left;vertical-align:top;padding:10px 12px}.lesson-content th{background:#ebe3d3}.lesson-content code{background:var(--code-bg);border-radius:4px;padding:.12em .3em;font-family:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;font-size:.94em}.lesson-content pre{color:#f7f4e8;background:#1f292b;border-radius:8px;margin:22px 0 28px;padding:16px;overflow-x:auto}.lesson-content pre code{color:inherit;background:0 0;padding:0}.katex-display{padding:4px 0 8px;overflow:auto hidden}.lesson-figure{margin:30px 0}.lesson-figure svg{width:100%;height:auto;display:block}.lesson-figure figcaption{color:var(--muted);margin-top:10px;font-size:.94rem}.exercise-gallery{border-top:1px solid 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