:root{--primary:#0B3D91;--primary-dark:#07285f;--ink:#152238;--muted:#667085;--line:#e5eaf2;--soft:#f5f8fc;--accent:#18b979;--white:#fff;--shadow:0 16px 45px rgba(18,45,86,.1)}
    *{box-sizing:border-box}
    html{scroll-behavior:smooth}
    body{margin:0;color:var(--ink);background:#f7f9fc;font-family:"PingFang SC","Microsoft YaHei",Arial,sans-serif;line-height:1.65}
    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:#071a3b;color:#cbd8ee;font-size:13px}
    .topbar .container{min-height:36px;display:flex;align-items:center;justify-content:space-between;gap:20px}
    .topbar a{margin-left:22px;color:#dbe8ff}
    .header{position:relative;z-index:20;background:var(--white);border-bottom:1px solid var(--line)}
    .header-inner{height:76px;display:flex;align-items:center;gap:34px}
    .logo{display:flex;align-items:center;gap:10px;color:var(--primary);font-weight:800;font-size:19px;white-space:nowrap}
    .logo img{width:34px;height:34px;object-fit:contain}
    .main-nav{flex:1}
    .nav-list{display:flex;align-items:stretch;justify-content:center;gap:3px;margin:0;padding:0;list-style:none}
    .nav-item{position:relative}
    .nav-link{height:76px;display:flex;align-items:center;padding:0 14px;color:#334155;font-size:15px;white-space:nowrap}
    .nav-link:hover,.nav-link:focus{color:var(--primary)}
    .has-arrow:after{content:"";width:6px;height:6px;margin:0 0 3px 8px;border-right:1px solid currentColor;border-bottom:1px solid currentColor;transform:rotate(45deg)}
    .dropdown-panel,.mega-menu{position:absolute;top:100%;left:50%;z-index:30;visibility:hidden;opacity:0;transform:translate(-50%,8px);transition:.22s ease;background:#fff;border:1px solid var(--line);border-radius:0 0 14px 14px;box-shadow:var(--shadow);padding:20px}
    .dropdown-panel{width:250px}
    .dropdown-panel a{display:block;padding:9px 10px;border-radius:7px;font-size:14px}
    .dropdown-panel a:hover{background:var(--soft);color:var(--primary)}
    .mega-menu{width:650px}
    .nav-item:hover>.mega-menu,.nav-item:focus-within>.mega-menu,.nav-item:hover>.dropdown-panel,.nav-item:focus-within>.dropdown-panel{visibility:visible;opacity:1;transform:translate(-50%,0)}
    .mega-menu:before{content:"";position:absolute;top:-12px;left:0;width:100%;height:12px}
    .mega-title{margin:0 0 12px;color:var(--primary-dark);font-size:14px;font-weight:800}
    .mega-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:10px}
    .mega-card{display:flex;gap:10px;padding:10px;border:1px solid #edf1f7;border-radius:10px;background:#fbfcfe;min-width:0}
    .mega-card:hover{border-color:#b9cae8;background:#f5f8fe}
    .mega-card img{width:38px;height:38px;border-radius:8px;object-fit:cover;flex:none}
    .mega-card b,.mega-card span{display:block;overflow:hidden;text-overflow:ellipsis}
    .mega-card b{font-size:13px;white-space:nowrap}
    .mega-card span span{color:var(--muted);font-size:11px;line-height:1.45;white-space:nowrap}
    .mega-links{display:flex;flex-wrap:wrap;gap:8px}
    .mega-links a{padding:6px 10px;border-radius:20px;background:var(--soft);font-size:13px;color:#475467}
    .mega-links a:hover{color:var(--primary);background:#e9f0fc}
    .mega-footer{display:block;margin-top:17px;padding-top:13px;border-top:1px solid var(--line);color:var(--primary);font-size:13px;font-weight:700}
    .header-btns{display:flex;align-items:center;gap:12px;white-space:nowrap;font-size:14px;color:var(--primary)}
    .account-btn{padding:9px 16px;color:#fff!important;background:var(--primary);border-radius:7px}
    .hamburger{display:none;border:0;background:none;padding:8px;cursor:pointer}
    .hamburger span{display:block;width:23px;height:2px;margin:5px 0;background:var(--ink);transition:.2s}
    .hamburger.active span:nth-child(1){transform:translateY(7px) rotate(45deg)}
    .hamburger.active span:nth-child(2){opacity:0}
    .hamburger.active span:nth-child(3){transform:translateY(-7px) rotate(-45deg)}
    .drawer-overlay{position:fixed;inset:0;z-index:40;background:rgba(5,19,43,.48);visibility:hidden;opacity:0;transition:.2s}
    .drawer-overlay.open{visibility:visible;opacity:1}
    .mobile-drawer{position:fixed;top:0;right:0;bottom:0;z-index:41;width:min(370px,88%);background:#fff;transform:translateX(100%);transition:.25s ease;overflow:auto}
    .mobile-drawer.open{transform:translateX(0)}
    .drawer-head{display:flex;align-items:center;gap:16px;padding:20px;border-bottom:1px solid var(--line);font-weight:700;color:var(--primary)}
    .drawer-head a{margin-left:auto;padding:7px 14px;background:var(--primary);color:#fff;border-radius:6px;font-size:13px}
    .drawer-close{border:0;background:none;font-size:28px;color:#667085;cursor:pointer;line-height:1}
    .drawer-menu{padding:12px 20px 30px}
    .drawer-link,.drawer-toggle{display:block;width:100%;padding:14px 0;border:0;border-bottom:1px solid #edf0f5;background:none;text-align:left;color:var(--ink);font-weight:600;cursor:pointer}
    .drawer-toggle:after{content:"+";float:right;color:var(--muted);font-size:20px;font-weight:400}
    .drawer-toggle.active:after{content:"−"}
    .drawer-submenu{max-height:0;overflow:hidden;transition:max-height .25s ease;padding-left:14px}
    .drawer-submenu.open{max-height:650px}
    .drawer-submenu a{display:block;padding:9px 0;color:var(--muted);font-size:14px}
    .footer{margin-top:70px;background:#071a3b;color:#b8c7df}
    .footer-grid{display:grid;grid-template-columns:1.5fr 1fr 1fr 1.1fr;gap:35px;padding:48px 0 38px}
    .footer h3,.footer h4{margin:0 0 16px;color:#fff}
    .footer h3{font-size:20px}
    .footer h4{font-size:14px}
    .footer p{margin:7px 0;font-size:13px}
    .footer-grid>div:not(.footer-brand) a{display:block;margin:8px 0;font-size:13px}
    .footer-grid a:hover{color:#fff}
    .footer-bottom{display:flex;justify-content:space-between;gap:20px;padding:18px 0;border-top:1px solid rgba(255,255,255,.14);font-size:12px;color:#8fa4c4}
    .video-page{padding:58px 0 20px}
    .page-heading{text-align:center;max-width:720px;margin:0 auto 34px}
    .eyebrow{display:inline-flex;align-items:center;gap:8px;color:var(--primary);font-size:13px;font-weight:800;letter-spacing:.12em}
    .eyebrow:before{content:"";width:22px;height:2px;background:var(--accent)}
    .page-heading h1{margin:12px 0 10px;font-size:clamp(30px,4vw,48px);line-height:1.2;color:#10264b}
    .page-heading p{margin:0;color:var(--muted);font-size:16px}
    .video-toolbar{display:flex;align-items:center;justify-content:space-between;gap:20px;margin-bottom:24px;padding:17px 20px;border:1px solid var(--line);border-radius:12px;background:#fff}
    .video-toolbar strong{color:#23395d}
    .video-filter{display:flex;flex-wrap:wrap;gap:8px}
    .video-filter a{padding:7px 14px;border:1px solid #dce4f0;border-radius:20px;color:#5c6d86;font-size:13px}
    .video-filter a:hover,.video-filter a.active{color:#fff;border-color:var(--primary);background:var(--primary)}
    .video-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:22px}
    .video-card{overflow:hidden;border:1px solid var(--line);border-radius:14px;background:#fff;box-shadow:0 7px 25px rgba(21,48,88,.05);transition:.2s}
    .video-card:hover{transform:translateY(-4px);box-shadow:var(--shadow)}
    .video-cover{position:relative;aspect-ratio:16/9;overflow:hidden;background:#dfe8f5}
    .video-cover img{width:100%;height:100%;object-fit:cover;transition:.3s}
    .video-card:hover .video-cover img{transform:scale(1.04)}
    .play-mark{position:absolute;left:18px;bottom:16px;width:42px;height:42px;display:grid;place-items:center;border-radius:50%;background:rgba(11,61,145,.92);color:#fff;font-size:18px;padding-left:2px}
    .duration{position:absolute;right:12px;bottom:12px;padding:3px 7px;border-radius:4px;background:rgba(0,0,0,.7);color:#fff;font-size:12px}
    .video-body{padding:18px 19px 20px}
    .video-body h2{margin:0 0 8px;font-size:18px;line-height:1.4;color:#182d50}
    .video-body h2 a:hover{color:var(--primary)}
    .video-summary{display:-webkit-box;-webkit-line-clamp:3;-webkit-box-orient:vertical;overflow:hidden;min-height:72px;margin:0;color:var(--muted);font-size:14px}
    .video-meta{display:flex;justify-content:space-between;gap:12px;margin-top:15px;padding-top:13px;border-top:1px solid #edf1f6;color:#8290a5;font-size:12px}
    .pagination{display:flex;justify-content:center;gap:8px;margin:38px 0 10px}
    .pagination a{min-width:36px;padding:7px 11px;text-align:center;border:1px solid #dce4f0;border-radius:6px;background:#fff;color:#53647d;font-size:13px}
    .pagination a:hover,.pagination a.current,.pagination a.active{color:#fff;background:var(--primary);border-color:var(--primary)}
    @media(max-width:1050px){
      .header-inner{gap:15px}.nav-link{padding:0 8px}.mega-menu{width:600px}
    }
    @media(max-width:800px){
      .container{width:min(100% - 28px,620px)}
      .topbar .container{padding:8px 0;align-items:flex-start;flex-direction:column;gap:2px}
      .topbar a{margin:0 14px 0 0}
      .main-nav{display:none}.hamburger{display:block}
      .header-inner{height:68px}.header-btns>a:first-child{display:none}
      .video-page{padding-top:38px}.video-toolbar{align-items:flex-start;flex-direction:column}
      .video-grid{grid-template-columns:repeat(2,1fr);gap:16px}
      .footer-grid{grid-template-columns:repeat(2,1fr);gap:25px}
      .footer-bottom{flex-direction:column}
    }
    @media(max-width:540px){
      .video-grid{grid-template-columns:1fr}.page-heading h1{font-size:32px}
      .video-body h2{font-size:17px}.footer-grid{grid-template-columns:1fr}
      .footer{margin-top:45px}
    }