:root{font-family:system-ui,-apple-system,Segoe UI,sans-serif;color:#17354e;background:#edf4f8}*{box-sizing:border-box}body{margin:0}button,input,a{font:inherit}button{cursor:pointer}.wrap{max-width:1100px;margin:auto;padding:0 20px}.top{background:white;border-bottom:1px solid #dce6ed}.top .wrap{display:flex;align-items:center;justify-content:space-between;min-height:68px}.brand{font-weight:800;color:#10365b;font-size:20px}.small{color:#60768a;font-size:13px}.hero{background:linear-gradient(115deg,rgba(8,37,69,.96),rgba(15,78,116,.78)),url('https://images.unsplash.com/photo-1464822759023-fed622ff2c3b?w=1600') center/cover;color:white;padding:54px 0 60px}.hero h1{font-size:clamp(30px,5vw,48px);margin:0 0 12px}.hero p{max-width:660px;line-height:1.6;margin:0}.section{margin:30px auto}.section h2{font-size:23px;color:#143c62;margin:0 0 16px}.grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:16px}.card{background:white;border:1px solid #dce6ed;border-radius:18px;overflow:hidden;box-shadow:0 4px 16px #173b5710}.cardbody{padding:20px}.card h3{margin:0 0 9px;color:#123d65}.card p{color:#63798a;font-size:14px;line-height:1.5}.tag{font-size:12px;font-weight:800;letter-spacing:.06em;color:#12699c}.btn{border:0;border-radius:10px;background:#0e598b;color:white;padding:11px 15px;font-weight:700;display:inline-block;text-decoration:none}.btn.secondary{background:#e8f2f9;color:#154f78}.actions{display:flex;gap:9px;flex-wrap:wrap;margin-top:15px}.videos{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:16px}.thumb{width:100%;aspect-ratio:16/9;object-fit:cover;background:#dbe7ee}.empty{padding:24px;background:#fff;border:1px dashed #b9cedd;border-radius:14px;color:#526d80}.search{width:100%;border:1px solid #bfd0db;border-radius:11px;padding:12px 14px;margin-bottom:15px}.video-title{font-size:15px;font-weight:700;margin:0 0 8px;line-height:1.4}.video-meta{color:#6c8292;font-size:12px}.nav{position:sticky;bottom:0;background:white;border-top:1px solid #dbe5eb;display:flex;justify-content:center;gap:12px;padding:9px;z-index:5}.nav button{border:0;background:transparent;color:#4c6a80;padding:10px 14px;border-radius:10px;font-weight:700}.nav button.active{background:#e5f1f8;color:#0c5888}.player{position:fixed;inset:0;background:#071522e8;display:flex;align-items:center;justify-content:center;padding:18px;z-index:20}.player-box{width:min(850px,100%);background:white;border-radius:16px;overflow:hidden}.player iframe{width:100%;aspect-ratio:16/9;border:0;display:block}.player-head{display:flex;justify-content:space-between;align-items:center;gap:10px;padding:12px 16px}.player-head button{border:0;background:#e7eff4;padding:9px 12px;border-radius:8px}.footer{padding:30px 0 85px;text-align:center;color:#6e8291;font-size:13px}.notice{font-size:13px;color:#597587}.study-icon{font-size:30px;margin-bottom:10px}@media(max-width:760px){.grid,.videos{grid-template-columns:1fr}.hero{padding:38px 0}.nav{gap:0;justify-content:space-around}.nav button{padding:10px}.top .wrap{min-height:60px}.section{margin:24px auto}}

/* Featured video follows the first item in each study playlist; clicking a card changes it. */
.featured-study{background:#fff;border:1px solid #dce6ed;border-radius:18px;padding:18px;margin:18px 0 22px;box-shadow:0 4px 16px #173b5710;scroll-margin-top:18px}.featured-heading h3{margin:8px 0 4px;color:#123d65;font-size:20px}.featured-iframe{display:block;width:100%;aspect-ratio:16/9;border:0;border-radius:12px;background:#071522;margin-top:14px}.selected-video{border:2px solid #db4e98;box-shadow:0 0 0 2px #fce2ef}.selected-video .video-title{color:#9b2466}