/* Lessons use the existing site's persisted dark/light colour tokens. */
.lesson-layout{max-width:1000px;padding-top:48px;padding-bottom:64px}.lesson-intro{max-width:780px;margin-bottom:42px}.lesson-intro h1,.lesson-article h1{font-size:clamp(30px,5vw,52px);line-height:1.2;letter-spacing:-.035em;margin:14px 0 20px}.lesson-intro>p:last-child{font-size:20px;color:var(--sp-muted)}.lesson-cards{display:grid;grid-template-columns:1fr 1fr;gap:20px}.lesson-card,.lesson-cta,.lesson-related{padding:28px;border:1px solid var(--sp-line);border-radius:18px;background:var(--sp-surface)}.lesson-card h2{margin:8px 0;font-size:25px}.lesson-card p{color:var(--sp-muted)}.lesson-card a,.lesson-cta a,.lesson-related a{color:var(--sp-accent)}.lesson-cta{margin-top:32px}.lesson-cta .button{color:var(--sp-button-text);background:var(--sp-accent)}.breadcrumbs,.lesson-byline{font-size:14px;color:var(--sp-muted)}.breadcrumbs{margin-bottom:28px}.lesson-article{max-width:760px;margin:auto;font-size:18px;line-height:1.85}.lesson-article h2{font-size:26px;line-height:1.35;margin-top:44px}.lesson-article p{overflow-wrap:anywhere}.lesson-article a{color:var(--sp-accent);text-underline-offset:4px}.lesson-byline{margin-bottom:30px}.worked-board{max-width:510px;margin:32px auto}.worked-board figcaption{font-size:14px;color:var(--sp-muted);margin-bottom:14px;line-height:1.6}.worked-board table{width:100%;table-layout:fixed;border-collapse:collapse;font-variant-numeric:tabular-nums;text-align:center;line-height:1.2}.worked-board td,.worked-board th{height:42px;padding:0;border:1px solid var(--sp-line)}.worked-board th{color:var(--sp-muted);font-size:13px;font-weight:500;background:var(--sp-bg)}.worked-board td{background:var(--sp-surface)}.worked-board .box-right{border-right-width:3px}.worked-board .box-bottom{border-bottom-width:3px}.worked-board .focus-cell{background:var(--sp-accent);color:var(--sp-button-text);font-weight:800;outline:2px solid var(--sp-orange);outline-offset:-3px}.number-example{font-size:clamp(15px,3.5vw,20px);font-variant-numeric:tabular-nums;white-space:pre-wrap;padding:18px;border-radius:12px;background:var(--sp-surface);color:var(--sp-text);border:1px solid var(--sp-line)}.lesson-related h2{margin-top:0}.lesson-related{margin-top:36px}.lesson-inlink{max-width:1000px;width:calc(100% - 40px);padding:24px;margin:24px auto;border:1px solid var(--sp-line);border-radius:16px;background:var(--sp-surface);color:var(--sp-text)}.lesson-inlink a{color:var(--sp-accent)}
@media(max-width:700px){.lesson-layout{padding-top:28px}.lesson-cards{grid-template-columns:1fr}.lesson-card,.lesson-cta,.lesson-related{padding:22px}.lesson-article{font-size:17px}.lesson-article h2{font-size:23px}.worked-board td,.worked-board th{height:32px}.lesson-layout .navlinks{gap:12px}}@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}}