/* Chapter route and optional step-by-step presentation. */
.math-hero{padding-block:42px;gap:48px}.hero-copy h1{font-size:clamp(2.4rem,5vw,3.8rem)}.math-notebook{min-height:320px;transform:none}.math-dashboard{margin-bottom:38px}
.course-tools{display:flex;justify-content:space-between;align-items:center;gap:18px;margin:20px 0}.course-parts{display:flex;gap:8px;flex-wrap:wrap}.course-parts button[aria-pressed=true]{background:var(--green);color:white;border-color:var(--green)}.course-select{display:grid;gap:6px;font-size:.75rem;color:var(--muted)}select{font:inherit;color:var(--ink);background:var(--white);padding:10px;border:1px solid #a4bbb1;border-radius:9px;max-width:100%}.course-reading-note{border-left:3px solid var(--green);padding:12px 18px;background:#eaf1e5;border-radius:0 12px 12px 0;margin:22px 0 32px}.course-reading-note strong{font-size:.86rem}.course-reading-note p{margin:6px 0 0;font-size:.82rem;color:var(--muted);max-width:730px}
.course-chapter{margin:35px 0 44px}.course-chapter-heading{margin-bottom:20px;max-width:740px}.course-chapter-heading .eyebrow{margin:0 0 8px}.course-chapter-heading h3{font-size:1.7rem;letter-spacing:-.04em;margin-bottom:8px}.course-chapter-heading p{color:var(--muted);font-size:.9rem;margin:0}.course-card .topic-number{background:#eaf1e5;padding:5px 8px;border-radius:7px}.course-card .topic-card-top{align-items:center}.course-card h3{font-size:1.07rem;line-height:1.45}.course-card p{line-height:1.7}.math-legacy{margin:36px 0;border:1px solid var(--line);border-radius:16px;padding:22px;background:#edf2e7}.math-legacy summary{cursor:pointer;font-weight:700;min-height:30px}.math-legacy>p{margin:17px 0 22px;color:var(--muted);font-size:.83rem}.math-legacy .topic-grid{margin-top:20px}
.lesson-content{line-height:1.8}.lesson-content h3{font-size:1.13rem;color:var(--ink)}.lesson-content>p{max-width:70ch}.lesson-visual{margin:22px 0;padding:16px;background:var(--paper);border-radius:14px;border:1px solid var(--line)}.lesson-visual figcaption{font-size:.75rem;line-height:1.5;color:var(--muted);margin-top:10px;text-align:center}.lesson-visual .math-visual{display:block;max-width:100%;width:320px;height:auto;margin:auto}.workspace-heading{flex-wrap:wrap}.workspace-heading .secondary{font-size:.78rem;margin-left:auto}.lesson-main{min-width:0}
.math-showcase{width:min(1060px,calc(100vw - 32px));max-width:1060px;max-height:94dvh;border:1px solid #b9cdbd;border-radius:20px;background:var(--paper);color:var(--ink);padding:20px;box-shadow:0 22px 70px #183d4330;overflow:auto}.math-showcase::backdrop{background:#183d438c}.showcase-toolbar{display:flex;align-items:center;justify-content:space-between;gap:15px;font-size:.75rem;font-weight:750;padding-bottom:10px}.showcase-options{display:flex;align-items:end;gap:10px;flex-wrap:wrap;margin-bottom:18px}.showcase-options label{display:grid;gap:6px;font-size:.72rem;color:var(--muted)}.showcase-options button{font-size:.75rem;min-height:42px}.showcase-paper{border-radius:15px;background:var(--white);border:1px solid var(--line);padding:24px 30px;position:relative}.showcase-brand{font-size:.83rem;color:var(--green);font-weight:750;text-decoration:none;display:block;margin-bottom:22px}.showcase-paper h2{font-size:clamp(1.35rem,3vw,2rem);line-height:1.3;overflow-wrap:anywhere}.showcase-paper .eyebrow{font-size:.66rem;margin-bottom:10px}.showcase-visual{float:right;margin:0 0 14px 20px;max-width:42%}.showcase-visual svg{width:280px;max-width:100%;height:auto}.showcase-question{font-weight:700;font-size:clamp(1.1rem,2.4vw,1.55rem);line-height:1.65;white-space:pre-line;overflow-wrap:anywhere}.showcase-paper ol{padding-left:25px;font-size:1.07rem;line-height:1.7;clear:both}.showcase-paper li{padding:7px 0}.showcase-paper li::marker{color:var(--green);font-weight:800}.showcase-answer{background:#d5eee2;padding:14px 18px;border-radius:10px;font-size:1.35rem;font-weight:800;color:#124b3c}.showcase-instruction{font-size:.8rem;color:var(--muted);margin-bottom:0}.showcase-actions{display:flex;justify-content:space-between;gap:8px;flex-wrap:wrap;margin:18px 0 10px}.showcase-actions button{font-size:.8rem}.showcase-note{font-size:.7rem;color:var(--muted);margin:12px 0 0}.math-showcase #showcase-status{font-size:.78rem;overflow-wrap:anywhere;min-height:1em;margin:10px 0 0}.math-showcase.is-portrait .showcase-paper{width:min(100%,390px);margin-inline:auto;min-height:693px;padding:24px}.math-showcase.is-portrait .showcase-visual{float:none;margin:16px 0 20px;max-width:100%}.math-showcase.is-portrait .showcase-visual svg{display:block;width:320px;margin:auto}.math-showcase.is-portrait h2{font-size:1.5rem}.math-showcase.is-portrait .showcase-question{font-size:1.2rem}.math-showcase.is-portrait .showcase-paper ol{font-size:1rem}.math-showcase:fullscreen{width:100%;max-width:none;max-height:none;height:100%;border-radius:0;padding:24px 5vw}.math-showcase:fullscreen .showcase-paper{max-width:1100px;margin-inline:auto}.math-showcase:fullscreen .showcase-options,.math-showcase:fullscreen .showcase-toolbar,.math-showcase:fullscreen .showcase-actions{max-width:1100px;margin-inline:auto}
@media(max-width:760px){.course-tools{align-items:start;flex-direction:column}.course-select{width:100%}.showcase-visual{float:none;max-width:100%;margin:14px 0}.showcase-visual svg{display:block;margin:auto}.math-showcase{padding:14px;width:calc(100vw - 16px);max-height:96dvh;border-radius:15px}.showcase-paper{padding:20px}.showcase-actions{justify-content:start}.showcase-actions .primary{flex:1}.showcase-toolbar{position:sticky;top:-14px;background:var(--paper);z-index:2}.course-chapter-heading h3{font-size:1.45rem}.math-legacy{padding:16px}}
@media(max-width:420px){.course-parts{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));width:100%;gap:6px}.course-parts button{padding:10px 7px;font-size:.74rem}.showcase-options button{flex:1}.showcase-options label{width:100%}.math-showcase.is-portrait .showcase-paper{padding:18px;min-height:520px}.showcase-paper ol{font-size:.92rem}.showcase-question{font-size:1.05rem}.workspace-heading>span{font-size:.7rem}.workspace-heading .secondary{width:100%;margin:0}.course-card{padding:19px}}
@media(prefers-reduced-motion:reduce){.math-showcase *{scroll-behavior:auto}}

.math-grade-switch{display:flex;justify-content:space-between;align-items:center;gap:18px;margin:28px 0 0;padding:18px 22px;background:#edf2e7;border:1px solid var(--line);border-radius:14px}.math-grade-switch .eyebrow{margin:0 0 5px}.math-grade-switch p{margin:0;font-size:.85rem}.math-grade-buttons{display:flex;gap:8px}.math-grade-buttons button{min-width:100px}.math-grade-buttons button[aria-pressed=true]{background:var(--green);color:white;border-color:var(--green)}@media(max-width:600px){.math-grade-switch{align-items:start;flex-direction:column;padding:16px}.math-grade-buttons{width:100%}.math-grade-buttons button{flex:1}}@media(max-width:420px){.course-parts.has-third{grid-template-columns:repeat(4,minmax(0,1fr))}}