main section h2{margin-top:2rem}main section h3{margin-top:1.25rem}main section ul li{line-height:1.7}.callout{margin-top:1.25rem}:root{--toc-sticky-top:84px}.toc{border:1px solid var(--border-color);background:var(--bg-primary);border-radius:var(--radius-lg);box-shadow:var(--shadow-sm);padding:1rem 1.25rem;position:sticky;top:var(--toc-sticky-top);z-index:10}.toc h2{font-size:1rem;margin-bottom:0.5rem;color:var(--text-secondary)}.toc ul{list-style:none;margin:0;padding:0;columns:2;column-gap:1.5rem}.toc li{break-inside:avoid;margin-bottom:0.35rem}.toc a{color:var(--text-secondary);text-decoration:none;font-size:0.95rem}.toc a:hover{color:var(--primary-color)}@media (width <= 768px){.toc{position:static}.toc ul{columns:1}}.two-col{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:1.5rem;margin:1rem 0 1.5rem}@media (width <= 768px){.two-col{grid-template-columns:1fr}}.feature-list{list-style:none;padding-left:0;display:grid;grid-template-columns:repeat(auto-fit,minmax(260px,1fr));gap:0.75rem 1rem;margin:0.75rem 0 1.5rem}.feature-list li{position:relative;padding-left:1.5rem}.feature-list li::before{content:'▹';position:absolute;left:0;color:var(--primary-color)}