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.chapter-heading{max-width:900px;margin-bottom:1.5rem}.chapter-heading h1{font-size:clamp(2rem,3.5vw,3.5rem);line-height:1.1;letter-spacing:-.035em}.chapter-heading p{max-width:70ch}
.chapter-demo{padding:.85rem 0;border-top:1px solid #dce3e9;border-bottom:1px solid #dce3e9;font-size:.9rem;color:#465664}
.chapter-layout{display:grid;grid-template-columns:minmax(220px,280px) minmax(0,1fr);gap:clamp(1.5rem,3vw,3rem);margin-top:2rem}.chapter-picker{border-right:1px solid #dce3e9;padding-right:1.5rem}.chapter-picker h2{font-size:1rem}.chapter-picker h3{font-size:.85rem;text-transform:uppercase;letter-spacing:.04em;margin-top:1.5rem}
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