:root{--primary:#0B3D91;--cyan:#0891B2;--ink:#172033;--muted:#667085;--line:#dce8ee;--soft:#effbfc;--white:#fff;--shadow:0 18px 45px rgba(15,54,78,.1)}
    *{box-sizing:border-box}
    html{scroll-behavior:smooth}
    body{margin:0;background:#f7fafc;color:var(--ink);font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","Noto Sans TC","PingFang TC",Arial,sans-serif;line-height:1.7}
    body,button,input{font:inherit}
    a{color:inherit;text-decoration:none}
    img{display:block;max-width:100%}
    button{color:inherit}
    .container{width:min(1180px,calc(100% - 40px));margin:auto}

    .topbar{background:#111827;color:#d8e4ea;font-size:13px}
    .topbar .container{min-height:38px;display:flex;align-items:center;justify-content:space-between;gap:20px}
    .topbar-links{display:flex;gap:20px}
    .topbar a:hover{color:#fff}

    .header{position:sticky;top:0;z-index:80;background:rgba(255,255,255,.97);border-bottom:1px solid var(--line);backdrop-filter:blur(14px)}
    .header-inner{min-height:76px;display:flex;align-items:center;gap:28px}
    .logo{display:flex;align-items:center;gap:10px;min-width:max-content;color:var(--primary);font-weight:800;font-size:20px}
    .logo img{width:42px;height:42px;object-fit:contain}
    .main-nav{flex:1}
    .nav-list{display:flex;align-items:center;justify-content:center;gap:3px;margin:0;padding:0;list-style:none}
    .nav-item{position:relative}
    .nav-link{display:flex;align-items:center;gap:6px;padding:25px 11px;font-size:14px;font-weight:700}
    .nav-link:hover{color:var(--cyan)}
    .has-arrow:after{content:"";width:6px;height:6px;border-right:1.5px solid currentColor;border-bottom:1.5px solid currentColor;transform:rotate(45deg) translateY(-2px)}
    .dropdown-panel,.mega-menu{position:absolute;top:calc(100% - 5px);left:50%;visibility:hidden;opacity:0;transform:translate(-50%,12px);transition:.2s ease;background:#fff;border:1px solid var(--line);border-radius:16px;box-shadow:var(--shadow)}
    .nav-item:hover .dropdown-panel,.nav-item:hover .mega-menu{visibility:visible;opacity:1;transform:translate(-50%,0)}
    .dropdown-panel{width:290px;padding:12px}
    .dropdown-panel>a{display:block;padding:10px 12px;border-radius:9px;font-size:14px}
    .dropdown-panel>a:hover{background:var(--soft);color:var(--primary)}
    .mega-menu{width:min(720px,80vw);padding:22px}
    .mega-title{margin:0 0 10px;color:var(--muted);font-size:12px;font-weight:800;letter-spacing:.08em}
    .mega-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:10px}
    .mega-card{min-width:0;padding:12px;border:1px solid var(--line);border-radius:11px}
    .mega-card:hover{border-color:var(--cyan);background:var(--soft)}
    .mega-card strong,.mega-card small{display:block;overflow:hidden;text-overflow:ellipsis}
    .mega-card strong{font-size:14px}
    .mega-card small{margin-top:4px;color:var(--muted);font-size:12px}
    .mega-card img{width:28px;height:28px;margin-bottom:8px;object-fit:contain}
    .mega-footer{display:block;margin-top:14px;padding:10px;border-radius:10px;background:var(--primary);color:#fff!important;text-align:center;font-weight:700}
    .header-btns{display:flex;align-items:center;gap:9px;min-width:max-content}
    .member-btn,.open-btn{padding:9px 15px;border-radius:9px;font-size:14px;font-weight:800}
    .member-btn{border:1px solid var(--primary);color:var(--primary)}
    .open-btn{background:var(--primary);color:#fff}
    .hamburger{display:none;width:42px;height:42px;padding:9px;border:1px solid var(--line);border-radius:10px;background:#fff;cursor:pointer}
    .hamburger span{display:block;height:2px;margin:5px 0;background:var(--ink);transition:.2s}

    .drawer-overlay{position:fixed;inset:0;z-index:98;visibility:hidden;opacity:0;background:rgba(15,23,42,.52);transition:.25s}
    .drawer-overlay.open{visibility:visible;opacity:1}
    .mobile-drawer{position:fixed;top:0;right:0;z-index:99;width:min(390px,90vw);height:100vh;overflow-y:auto;background:#fff;transform:translateX(105%);transition:.28s ease}
    .mobile-drawer.open{transform:translateX(0)}
    .drawer-head{display:flex;align-items:center;gap:10px;padding:18px;border-bottom:1px solid var(--line)}
    .drawer-head>a{padding:8px 12px;border-radius:8px;background:var(--primary);color:#fff;font-size:14px}
    .drawer-close{margin-left:auto;border:0;background:none;font-size:30px;cursor:pointer}
    .drawer-menu{padding:12px 18px 30px}
    .drawer-link,.drawer-toggle{display:block;width:100%;padding:13px 4px;border:0;border-bottom:1px solid var(--line);background:none;text-align:left;font-weight:750;cursor:pointer}
    .drawer-toggle:after{content:"+";float:right}
    .drawer-toggle.active:after{content:"−"}
    .drawer-submenu{display:none;padding:6px 0 8px 14px}
    .drawer-submenu.open{display:block}
    .drawer-submenu a{display:block;padding:9px;color:var(--muted);font-size:14px}

    .video-detail-main{min-width:0}
    .video-detail-main .video-heading{padding:62px 0 28px;background:linear-gradient(135deg,#eaf9fb 0%,#f8fbff 55%,#e7effd 100%);border-bottom:1px solid var(--line)}
    .video-detail-main .breadcrumb{display:flex;flex-wrap:wrap;gap:8px;margin-bottom:18px;color:var(--muted);font-size:14px}
    .video-detail-main .breadcrumb a:hover{color:var(--primary)}
    .video-detail-main .category-label{display:inline-flex;align-items:center;gap:7px;margin-bottom:12px;padding:5px 11px;border-radius:99px;background:#d9f4f6;color:#076f85;font-size:13px;font-weight:800}
    .video-detail-main .category-label:before{content:"";width:7px;height:7px;border-radius:50%;background:var(--cyan)}
    .video-detail-main h1{max-width:950px;margin:0;font-size:clamp(30px,5vw,52px);line-height:1.16;letter-spacing:-.025em}
    .video-detail-main .video-meta{display:flex;flex-wrap:wrap;gap:10px 22px;margin-top:19px;color:var(--muted);font-size:14px}
    .video-detail-main .video-meta span{display:flex;align-items:center;gap:6px}
    .video-detail-main .video-layout{display:grid;grid-template-columns:minmax(0,1fr) 320px;gap:28px;padding-top:36px;padding-bottom:68px}
    .video-detail-main .video-primary{min-width:0}
    .video-detail-main .player-shell{position:relative;min-height:420px;overflow:hidden;border-radius:20px;background:#090f1d;box-shadow:var(--shadow)}
    .video-detail-main .player-shell>*{max-width:100%}
    .video-detail-main .player-shell iframe,.video-detail-main .player-shell video{display:block;width:100%;min-height:500px;border:0}
    .video-detail-main .video-summary,.video-detail-main .video-body,.video-detail-main .related-section,.video-detail-main .video-sidebar{margin-top:24px;padding:26px;background:#fff;border:1px solid var(--line);border-radius:18px;box-shadow:0 10px 30px rgba(15,54,78,.05)}
    .video-detail-main .video-summary h2,.video-detail-main .video-body h2,.video-detail-main .related-head h2,.video-detail-main .video-sidebar h2{margin:0 0 12px;font-size:22px}
    .video-detail-main .video-summary p{margin:0;color:#465267;font-size:16px}
    .video-detail-main .video-body{min-width:0;max-width:100%;overflow-x:auto}
    .video-detail-main .video-body img,.video-detail-main .video-body video,.video-detail-main .video-body iframe,.video-detail-main .video-body table{max-width:100%}
    .video-detail-main .video-body table{width:100%;border-collapse:collapse}
    .video-detail-main .video-tags{display:flex;flex-wrap:wrap;gap:8px;margin-top:20px;padding-top:18px;border-top:1px solid var(--line)}
    .video-detail-main .video-tags strong{color:var(--muted);font-size:14px}
    .video-detail-main .tag-content{color:var(--primary)}
    .video-detail-main .video-sidebar{align-self:start;margin-top:0;position:sticky;top:102px}
    .video-detail-main .sidebar-cover{overflow:hidden;margin-bottom:20px;border-radius:13px;background:var(--soft);aspect-ratio:16/10}
    .video-detail-main .sidebar-cover img{width:100%;height:100%;object-fit:cover}
    .video-detail-main .info-list{margin:0;padding:0;list-style:none}
    .video-detail-main .info-list li{display:flex;justify-content:space-between;gap:20px;padding:11px 0;border-bottom:1px solid var(--line);font-size:14px}
    .video-detail-main .info-list span{color:var(--muted)}
    .video-detail-main .more-video-btn{display:block;margin-top:20px;padding:12px;border-radius:10px;background:var(--primary);color:#fff;text-align:center;font-weight:800}
    .video-detail-main .related-head{display:flex;align-items:center;justify-content:space-between;gap:15px;margin-bottom:18px}
    .video-detail-main .related-head h2{margin:0}
    .video-detail-main .related-head a{color:var(--primary);font-size:14px;font-weight:800}
    .video-detail-main .related-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:16px}
    .video-detail-main .related-card{min-width:0;overflow:hidden;border:1px solid var(--line);border-radius:14px;background:#fff;transition:.2s}
    .video-detail-main .related-card:hover{transform:translateY(-3px);border-color:var(--cyan);box-shadow:0 12px 26px rgba(8,145,178,.12)}
    .video-detail-main .related-cover{position:relative;aspect-ratio:16/9;overflow:hidden;background:#dce8ee}
    .video-detail-main .related-cover img{width:100%;height:100%;object-fit:cover}
    .video-detail-main .related-duration{position:absolute;right:8px;bottom:8px;padding:2px 7px;border-radius:5px;background:rgba(0,0,0,.75);color:#fff;font-size:12px}
    .video-detail-main .related-card-body{padding:14px}
    .video-detail-main .related-card h3{display:-webkit-box;overflow:hidden;margin:0;font-size:15px;line-height:1.45;-webkit-box-orient:vertical;-webkit-line-clamp:2}
    .video-detail-main .related-card p{display:-webkit-box;overflow:hidden;margin:8px 0 0;color:var(--muted);font-size:13px;-webkit-box-orient:vertical;-webkit-line-clamp:2}

    .footer{background:#111827;color:#cbd5e1}
    .footer-grid{display:grid;grid-template-columns:1.5fr repeat(3,1fr);gap:45px;padding:58px 0 42px}
    .footer h3,.footer strong{color:#fff}
    .footer h3{margin:0 0 15px;font-size:16px}
    .footer p{color:#94a3b8;font-size:14px}
    .footer-grid>div>a,.footer-grid>div>span{display:block;margin:9px 0;color:#aebdca;font-size:14px}
    .footer a:hover{color:#fff}
    .footer-bottom{display:flex;justify-content:space-between;gap:25px;padding:20px 0;border-top:1px solid #2a3545;color:#94a3b8;font-size:13px}

    @media(max-width:1050px){
      .main-nav{display:none}
      .hamburger{display:block}
      .header-inner{justify-content:space-between}
      .video-detail-main .video-layout{grid-template-columns:1fr}
      .video-detail-main .video-sidebar{position:static}
      .footer-grid{grid-template-columns:repeat(2,1fr)}
    }
    @media(max-width:720px){
      .container{width:min(100% - 28px,1180px)}
      .topbar .container{min-height:44px}
      .topbar-links{display:none}
      .header-inner{min-height:68px}
      .logo span{font-size:17px}
      .logo img{width:36px;height:36px}
      .member-btn{display:none}
      .open-btn{padding:8px 11px}
      .video-detail-main .video-heading{padding:42px 0 22px}
      .video-detail-main .video-layout{gap:18px;padding-top:22px;padding-bottom:45px}
      .video-detail-main .player-shell{min-height:220px;border-radius:14px}
      .video-detail-main .player-shell iframe,.video-detail-main .player-shell video{min-height:230px}
      .video-detail-main .video-summary,.video-detail-main .video-body,.video-detail-main .related-section,.video-detail-main .video-sidebar{padding:19px;border-radius:14px}
      .video-detail-main .related-grid{grid-template-columns:1fr}
      .mega-grid{grid-template-columns:1fr}
      .footer-grid{grid-template-columns:1fr;gap:25px;padding:42px 0 30px}
      .footer-bottom{flex-direction:column;gap:8px}
    }