:root{
      --primary:#0B3D91;
      --primary-dark:#082b67;
      --ink:#182235;
      --muted:#64748b;
      --line:#dce4ee;
      --soft:#f4f7fb;
      --white:#fff;
      --shadow:0 18px 50px rgba(15,35,70,.1);
      --radius:18px;
    }
    *{box-sizing:border-box}
    html{scroll-behavior:smooth}
    body{margin:0;color:var(--ink);font-family:system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI","Noto Sans TC",Arial,sans-serif;background:#f7f9fc;line-height:1.7}
    a{color:inherit;text-decoration:none}
    img{max-width:100%;display:block}
    button{font:inherit}
    .container{width:min(1180px,calc(100% - 40px));margin:0 auto}
    .topbar{background:#101c33;color:#d8e2f4;font-size:13px}
    .topbar-inner{min-height:36px;display:flex;align-items:center;justify-content:space-between;gap:20px}
    .topbar-links{display:flex;gap:20px}
    .topbar a{color:#e8eef8}
    .header{position:relative;z-index:20;background:rgba(255,255,255,.97);border-bottom:1px solid var(--line)}
    .header-inner{height:76px;display:flex;align-items:center;gap:30px}
    .logo{display:inline-flex;align-items:center;gap:10px;font-size:20px;font-weight:800;white-space:nowrap;color:var(--primary-dark)}
    .logo img{width:34px;height:34px;object-fit:contain}
    .main-nav{flex:1}
    .nav-list{display:flex;align-items:stretch;justify-content:center;gap:4px;list-style:none;padding:0;margin:0}
    .nav-item{position:relative}
    .nav-link{display:flex;align-items:center;gap:6px;padding:26px 13px;font-size:15px;font-weight:650;white-space:nowrap}
    .nav-link:hover,.nav-link:focus{color:var(--primary)}
    .has-arrow:after{content:"⌄";font-size:13px;color:#8290a4}
    .dropdown-panel,.mega-menu{position:absolute;left:50%;top:calc(100% + 1px);transform:translateX(-50%) translateY(8px);width:300px;padding:20px;background:#fff;border:1px solid var(--line);border-radius:0 0 16px 16px;box-shadow:var(--shadow);opacity:0;visibility:hidden;transition:.2s;z-index:30}
    .mega-menu{width:580px}
    .nav-item:hover>.dropdown-panel,.nav-item:focus-within>.dropdown-panel,.nav-item:hover>.mega-menu,.nav-item:focus-within>.mega-menu{opacity:1;visibility:visible;transform:translateX(-50%) translateY(0)}
    .dropdown-panel:before,.mega-menu:before{content:"";position:absolute;left:0;right:0;top:-12px;height:12px}
    .mega-title{margin:0 0 13px;color:var(--primary);font-size:13px;font-weight:800;letter-spacing:.08em}
    .dropdown-list{display:grid;gap:9px}
    .dropdown-list a{font-size:14px;color:#40506a;padding:5px 0}
    .dropdown-list a:hover{color:var(--primary)}
    .mega-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:10px}
    .mega-card{display:flex;gap:10px;min-width:0;padding:10px;border:1px solid #e6ebf2;border-radius:11px;background:#fbfcfe}
    .mega-card:hover{border-color:#9bb3d9;background:#f2f6fc}
    .mega-card img{width:38px;height:38px;object-fit:cover;border-radius:8px;background:#edf2f8;flex:0 0 auto}
    .mega-card span{min-width:0}
    .mega-card strong,.mega-card small{display:block;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
    .mega-card strong{font-size:13px}
    .mega-card small{font-size:11px;color:var(--muted);line-height:1.5}
    .mega-footer{display:block;margin-top:16px;padding-top:13px;border-top:1px solid var(--line);font-size:13px;color:var(--primary);font-weight:700}
    .header-btns{display:flex;align-items:center;gap:13px;white-space:nowrap}
    .member-link{font-size:14px;color:var(--primary);font-weight:700}
    .open-account{padding:9px 17px;border-radius:9px;background:var(--primary);color:#fff;font-size:14px;font-weight:700}
    .open-account:hover{background:var(--primary-dark)}
    .hamburger{display:none;width:42px;height:40px;border:1px solid var(--line);border-radius:9px;background:#fff;cursor:pointer;padding:8px}
    .hamburger span{display:block;height:2px;margin:5px 0;background:var(--ink);transition:.2s}
    .drawer-overlay{position:fixed;inset:0;background:rgba(8,19,39,.52);opacity:0;visibility:hidden;transition:.2s;z-index:50}
    .drawer-overlay.open{opacity:1;visibility:visible}
    .mobile-drawer{position:fixed;top:0;right:0;width:min(390px,88vw);height:100vh;overflow:auto;background:#fff;transform:translateX(105%);transition:.25s;z-index:60;box-shadow:-12px 0 35px rgba(0,0,0,.18)}
    .mobile-drawer.open{transform:translateX(0)}
    .drawer-head{display:flex;align-items:center;gap:14px;padding:20px;border-bottom:1px solid var(--line);font-weight:800}
    .drawer-head>a{margin-left:auto;color:var(--primary);font-size:14px}
    .drawer-close{border:0;background:none;font-size:28px;line-height:1;cursor:pointer;color:#607089}
    .drawer-menu{padding:12px 20px 30px}
    .drawer-link,.drawer-toggle{display:block;width:100%;padding:14px 0;border:0;border-bottom:1px solid #edf1f5;background:none;text-align:left;font-weight:700;color:var(--ink);cursor:pointer}
    .drawer-toggle:after{content:"＋";float:right;color:var(--primary)}
    .drawer-toggle.active:after{content:"－"}
    .drawer-submenu{display:none;padding:5px 0 7px 14px;border-bottom:1px solid #edf1f5}
    .drawer-submenu.open{display:block}
    .drawer-submenu a{display:block;padding:7px 0;color:var(--muted);font-size:14px}
    .footer{margin-top:70px;background:#101c33;color:#cbd6e8}
    .footer-grid{display:grid;grid-template-columns:1.5fr 1fr 1fr 1fr;gap:38px;padding:52px 0 38px}
    .footer-brand .logo{color:#fff;margin-bottom:15px}
    .footer-brand p,.footer-col p{margin:0;color:#aebbd0;font-size:14px}
    .footer-col h3{margin:0 0 14px;color:#fff;font-size:15px}
    .footer-links{list-style:none;padding:0;margin:0;display:grid;gap:8px}
    .footer-links a{font-size:14px;color:#b9c6d9}
    .footer-links a:hover{color:#fff}
    .footer-bottom{display:flex;justify-content:space-between;gap:20px;padding:19px 0;border-top:1px solid rgba(255,255,255,.12);font-size:12px;color:#9eacc1}
    .video-detail-main{padding:54px 0 10px}
    .video-breadcrumb{display:flex;align-items:center;gap:9px;margin-bottom:22px;color:var(--muted);font-size:14px}
    .video-breadcrumb a{color:var(--primary)}
    .video-layout{display:grid;grid-template-columns:minmax(0,1fr) 310px;gap:28px;align-items:start}
    .video-main-card{background:#fff;border:1px solid var(--line);border-radius:var(--radius);box-shadow:var(--shadow);overflow:hidden}
    .video-player{position:relative;aspect-ratio:16/9;background:#111b2e;display:flex;align-items:center;justify-content:center;overflow:hidden}
    .video-player img{width:100%;height:100%;object-fit:cover;opacity:.78}
    .video-player:after{content:"";position:absolute;inset:0;background:linear-gradient(180deg,rgba(8,19,39,.05),rgba(8,19,39,.7))}
    .video-play{position:absolute;z-index:2;width:76px;height:76px;border:1px solid rgba(255,255,255,.75);border-radius:50%;background:rgba(11,61,145,.86);color:#fff;font-size:31px;padding-left:7px;cursor:pointer;box-shadow:0 10px 30px rgba(0,0,0,.28)}
    .video-duration{position:absolute;z-index:2;right:18px;bottom:15px;padding:3px 9px;border-radius:6px;background:rgba(0,0,0,.7);color:#fff;font-size:12px}
    .video-content{padding:30px 34px 35px;min-width:0;max-width:100%;overflow-x:auto}
    .video-content h1{margin:0 0 14px;font-size:clamp(26px,4vw,42px);line-height:1.25;color:#142442}
    .video-meta{display:flex;flex-wrap:wrap;gap:12px 20px;padding-bottom:20px;border-bottom:1px solid var(--line);color:var(--muted);font-size:13px}
    .video-summary{margin:24px 0;padding:18px 20px;border-left:4px solid var(--primary);border-radius:0 10px 10px 0;background:#f3f7fc;color:#43536b}
    .video-body{min-width:0;max-width:100%;overflow-x:auto;font-size:16px;color:#334155}
    .video-body img,.video-body table{max-width:100%;height:auto}
    .video-tags{display:flex;flex-wrap:wrap;gap:8px;margin-top:26px}
    .video-tags a{padding:5px 11px;border-radius:20px;background:#edf3fb;color:var(--primary);font-size:13px}
    .video-side{display:grid;gap:20px}
    .side-card{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:22px;box-shadow:0 8px 25px rgba(15,35,70,.06)}
    .side-card h2{margin:0 0 16px;font-size:18px;color:#172945}
    .side-card p{margin:0;color:var(--muted);font-size:14px}
    .side-video{display:grid;grid-template-columns:100px 1fr;gap:11px;padding:12px 0;border-bottom:1px solid #edf1f5}
    .side-video:last-child{border-bottom:0;padding-bottom:0}
    .side-video:first-of-type{padding-top:0}
    .side-video img{width:100px;height:64px;object-fit:cover;border-radius:8px;background:#e8eef7}
    .side-video strong{display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden;font-size:13px;line-height:1.45}
    .side-video small{display:block;color:var(--muted);font-size:11px;margin-top:4px}
    .video-actions{display:flex;flex-wrap:wrap;gap:10px;margin-top:28px;padding-top:22px;border-top:1px solid var(--line)}
    .video-actions a{padding:9px 15px;border-radius:8px;background:#eef3fa;color:var(--primary);font-size:14px;font-weight:700}
    .video-actions a.primary{background:var(--primary);color:#fff}
    @media(max-width:1050px){
      .nav-link{padding-left:8px;padding-right:8px;font-size:14px}
      .member-link{display:none}
      .mega-menu{width:510px}
    }
    @media(max-width:820px){
      .container{width:min(100% - 28px,680px)}
      .topbar-inner{padding:7px 0;align-items:flex-start}
      .topbar-links{gap:8px;flex-direction:column;align-items:flex-end}
      .header-inner{height:66px}
      .main-nav{display:none}
      .hamburger{display:block}
      .header-btns{margin-left:auto}
      .footer-grid{grid-template-columns:1fr 1fr;gap:28px}
      .footer-bottom{flex-direction:column;gap:6px}
      .video-detail-main{padding-top:30px}
      .video-layout{grid-template-columns:1fr}
      .video-side{grid-template-columns:1fr 1fr}
    }
    @media(max-width:560px){
      .topbar{font-size:11px}
      .topbar-links{font-size:11px}
      .open-account{display:none}
      .footer-grid{grid-template-columns:1fr}
      .video-content{padding:23px 20px 27px}
      .video-content h1{font-size:27px}
      .video-side{grid-template-columns:1fr}
      .video-play{width:60px;height:60px;font-size:25px}
    }