img,iframe{max-width:100%;height:auto} html,body{-webkit-text-size-adjust:100%;text-size-adjust:100%} .course-page{padding:40px 0 60px;} .content-section{background:#fff;border:1px solid #e2e8f0;border-radius:12px;margin-bottom:20px;overflow:hidden;box-shadow:0 1px 4px rgba(0,0,0,.05);} .content-section-header{display:flex;align-items:center;gap:14px;padding:18px 24px;border-bottom:1px solid #f1f5f9;background:#f8fafc;} .section-icon{width:36px;height:36px;border-radius:8px;background:linear-gradient(135deg,#1ba2b6,#1acbdd);display:flex;align-items:center;justify-content:center;flex-shrink:0;font-size:1rem;color:#fff;} .content-section-header h3{margin:0;font-size:1.05rem;color:#232323;font-weight:700;} .content-section-body{padding:20px 24px;} .intro-video{display:flex;align-items:center;gap:20px;flex-wrap:wrap;} .intro-video a{display:block;border-radius:10px;overflow:hidden;box-shadow:0 2px 10px rgba(0,0,0,.15);transition:transform .15s;} .intro-video a:hover{transform:scale(1.02);} .intro-video img{display:block;width:280px;height:auto;} .intro-video p{color:#475569;font-size:.93rem;margin:0;line-height:1.6;} .chapter-list{list-style:none;padding:0;margin:0;} .chapter-list>li{border-top:1px solid #f1f5f9;margin:0;} .chapter-list>li:first-child{border-top:none;} .chapter-btn{display:flex;align-items:center;gap:14px;padding:11px 8px;border-radius:8px;text-decoration:none;color:#232323;transition:background .15s;} .chapter-btn:hover{background:#f0fdfa;} .chapter-btn:hover .chapter-title{color:#1ba2b6;} .chapter-btn:focus-visible{outline:2px solid #1ba2b6;outline-offset:2px;} .chapter-list .chapter-num{width:34px;height:34px;flex-shrink:0;border-radius:8px;background:linear-gradient(135deg,#1ba2b6,#1acbdd);color:#fff;font-size:.9rem;font-weight:700;line-height:34px;text-align:center;display:block;} .chapter-title{flex:1;font-size:.92rem;font-weight:600;line-height:1.4;transition:color .15s;} .chapter-btn-sub{display:block;font-size:.78rem;font-weight:400;color:#64748b;margin-top:2px;} .chapter-arrow{flex-shrink:0;color:#1ba2b6;font-size:1.15rem;font-weight:700;opacity:0;transform:translateX(-4px);transition:opacity .15s,transform .15s;} .chapter-btn:hover .chapter-arrow{opacity:1;transform:none;} @media (max-width:640px){.chapter-arrow{opacity:.6;transform:none;}} @media (prefers-reduced-motion:reduce){.chapter-btn,.chapter-title,.chapter-arrow{transition:none;}} .video-link-list{list-style:none;padding:0;margin:0;columns:2;gap:0;} @media (max-width:640px){.video-link-list{columns:1;}} .video-link-list li{break-inside:avoid;padding:7px 0;border-bottom:1px solid #f1f5f9;margin:0;} .video-link-list li a{font-size:.88rem;color:#1ba2b6;font-weight:500;display:flex;align-items:center;gap:6px;text-decoration:none;} .video-link-list li a:hover{text-decoration:underline;} .video-link-list li a::before{content:'▶';font-size:.65rem;color:#1acbdd;flex-shrink:0;} .test-cta{background:linear-gradient(135deg,#1ba2b6 0%,#1acbdd 100%);border-radius:10px;padding:18px 22px;margin-top:20px;display:flex;align-items:center;justify-content:space-between;gap:16px;flex-wrap:wrap;} .test-cta p{margin:0;color:#fff;font-size:.95rem;font-weight:500;} .test-cta em{opacity:.85;font-style:normal;} .test-cta .btn{background:#fff;color:#1ba2b6;font-weight:700;margin:0;min-width:0;padding:10px 20px;font-size:.9rem;text-shadow:none;} .course-disclaimer{background:#f8fafc;border:1px solid #e2e8f0;border-radius:10px;padding:18px 22px;margin-top:20px;font-size:.82rem;color:#64748b;line-height:1.6;} .course-disclaimer p{margin:0 0 8px;} .course-disclaimer p:last-child{margin:0;} .course-disclaimer strong{display:block;color:#475569;font-size:.85rem;margin-bottom:6px;} .course-h2{color:#232323;font-size:1.25rem;font-weight:700;margin:26px 0 12px;} .course-h3{color:#232323;font-size:1.05rem;font-weight:700;margin:20px 0 10px;} .course-figure{margin:18px 0;} .course-figure img{max-width:100%;height:auto;display:block;border-radius:8px;border:1px solid #e2e8f0;} .course-figure figcaption{font-size:.8rem;color:#64748b;margin-top:8px;} .pro-tip{background:#f0fdfa;border-left:4px solid #1acbdd;padding:12px 16px;border-radius:0 6px 6px 0;margin:16px 0;} .course-nav{display:flex;justify-content:space-between;align-items:center;gap:12px;flex-wrap:wrap;margin:24px 0 8px;}