.math-themes-section{background:#f9fafc;padding:4rem 2rem}.section-title.centered{display:flex;justify-content:center;margin-bottom:3rem}.section-title.centered h2{color:#1e1e2f;font-family:STIX Two Text,serif;font-size:2rem;font-weight:600;position:relative}.section-title.centered h2:after{background:#4f46e5;border-radius:2px;bottom:-10px;content:"";height:3px;left:50%;position:absolute;transform:translateX(-50%);width:80px}.themes-grid{display:grid;gap:2rem;grid-template-columns:repeat(auto-fit,minmax(260px,1fr));margin:0 auto;max-width:1200px}.theme-card{background:#fff;border-radius:14px;box-shadow:0 10px 25px rgba(0,0,0,.06);color:inherit;display:block;padding:2rem 1.6rem;text-decoration:none;transition:transform .25s ease,box-shadow .25s ease}.theme-card:hover{box-shadow:0 18px 40px rgba(0,0,0,.08);transform:translateY(-6px)}.theme-icon{color:#4f46e5;display:block;font-size:3rem;margin-bottom:.8rem}.theme-card h3{color:#2b2b44;font-family:STIX Two Text,serif;font-size:1.3rem;margin-bottom:.8rem}.theme-card ul{list-style:none;margin:0;padding:0}.theme-card li{font-size:.95rem;padding:.35rem 0 .35rem 1.1rem;position:relative}.theme-card li:before{color:#4f46e5;content:"•";font-weight:700;left:0;position:absolute}