:root{
      --primary:#0B3D91;
      --primary-dark:#082d6b;
      --ink:#142033;
      --muted:#667085;
      --line:#e5eaf1;
      --soft:#f4f7fb;
      --white:#fff;
      --shadow:0 18px 50px rgba(20,32,51,.10);
    }
    *{box-sizing:border-box}
    html{scroll-behavior:smooth}
    body{margin:0;color:var(--ink);font-family:"Microsoft YaHei","PingFang SC",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:auto}
    .topbar{background:#081b3c;color:#d9e5fb;font-size:13px}
    .topbar .container{height:38px;display:flex;align-items:center;justify-content:space-between}
    .topbar-links{display:flex;gap:24px}
    .topbar a:hover{color:#fff}
    .header{height:76px;background:#fff;border-bottom:1px solid var(--line);position:relative;z-index:20}
    .header-inner{height:100%;display:flex;align-items:center;gap:32px}
    .logo{display:flex;align-items:center;gap:10px;min-width:190px;font-weight:800;color:var(--primary);font-size:19px}
    .logo img{width:38px;height:38px;object-fit:contain}
    .main-nav{flex:1}
    .nav-list{display:flex;align-items:stretch;justify-content:center;gap:4px;padding:0;margin:0;list-style:none;height:76px}
    .nav-item{position:relative;display:flex;align-items:center}
    .nav-link{display:flex;align-items:center;height:76px;padding:0 14px;color:#26364f;font-size:15px;white-space:nowrap}
    .nav-link:hover,.nav-link:focus{color:var(--primary)}
    .has-arrow:after{content:"";width:6px;height:6px;border-right:1px solid currentColor;border-bottom:1px solid currentColor;transform:rotate(45deg);margin:0 0 4px 8px}
    .dropdown-panel,.mega-menu{position:absolute;top:100%;left:50%;transform:translateX(-50%);opacity:0;visibility:hidden;pointer-events:none;transition:.2s;background:#fff;border:1px solid var(--line);box-shadow:var(--shadow);z-index:30}
    .dropdown-panel{width:280px;padding:12px;border-radius:0 0 12px 12px}
    .dropdown-panel a{display:block;padding:10px 12px;border-radius:7px;font-size:14px}
    .dropdown-panel a:hover{background:var(--soft);color:var(--primary)}
    .mega-menu{width:760px;padding:20px;border-radius:0 0 16px 16px}
    .nav-item:after{content:"";position:absolute;left:0;right:0;height:14px;top:100%}
    .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;pointer-events:auto}
    .mega-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:12px}
    .mega-card{display:grid;grid-template-columns:42px 1fr;column-gap:10px;padding:10px;border:1px solid var(--line);border-radius:10px}
    .mega-card:hover{border-color:#aac0e4;background:#f7faff}
    .mega-card img{width:42px;height:42px;object-fit:cover;border-radius:8px;grid-row:span 3}
    .mega-card strong{font-size:13px;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
    .mega-card small{color:var(--muted);font-size:11px;line-height:1.5}
    .mega-footer{display:flex;flex-wrap:wrap;gap:12px;margin-top:16px;padding-top:14px;border-top:1px solid var(--line);color:var(--primary);font-size:13px}
    .header-btns{display:flex;align-items:center;gap:10px;white-space:nowrap}
    .member-link{font-size:13px;color:var(--primary)}
    .open-account{background:var(--primary);color:#fff;padding:8px 15px;border-radius:7px;font-size:13px}
    .open-account:hover{background:var(--primary-dark)}
    .hamburger{display:none;border:0;background:transparent;padding:7px;cursor:pointer}
    .hamburger span{display:block;width:24px;height:2px;background:var(--ink);margin:5px 0;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;background:rgba(2,14,35,.52);opacity:0;visibility:hidden;transition:.2s;z-index:40}
    .drawer-overlay.open{opacity:1;visibility:visible}
    .mobile-drawer{position:fixed;top:0;right:-360px;width:min(360px,88vw);height:100vh;background:#fff;z-index:50;transition:.28s;overflow-y:auto;box-shadow:-15px 0 40px rgba(0,0,0,.15)}
    .mobile-drawer.open{right:0}
    .drawer-head{display:flex;align-items:center;gap:14px;padding:20px;border-bottom:1px solid var(--line)}
    .drawer-head strong{flex:1;color:var(--primary)}
    .drawer-head a{background:var(--primary);color:#fff;padding:6px 12px;border-radius:6px;font-size:13px}
    .drawer-close{border:0;background:transparent;font-size:28px;line-height:1;cursor:pointer;color:var(--muted)}
    .drawer-menu{padding:10px 20px 30px}
    .drawer-link,.drawer-toggle{display:block;width:100%;padding:14px 0;border:0;border-bottom:1px solid var(--line);background:transparent;text-align:left;color:var(--ink);cursor:pointer}
    .drawer-toggle:after{content:"+";float:right;color:var(--primary);font-size:20px}
    .drawer-toggle.active:after{content:"−"}
    .drawer-submenu{max-height:0;overflow:hidden;transition:.25s;padding-left:15px}
    .drawer-submenu.open{max-height:600px}
    .drawer-submenu a{display:block;padding:9px 0;color:var(--muted);font-size:14px}
    .footer{background:#081b3c;color:#c5d2e8;margin-top:70px}
    .footer .container{padding:48px 0 20px}
    .footer-grid{display:grid;grid-template-columns:1.5fr 1fr 1fr 1.2fr;gap:35px}
    .footer h3{font-size:15px;color:#fff;margin:0 0 15px}
    .footer-brand strong{font-size:20px;color:#fff}
    .footer p{margin:8px 0;font-size:13px}
    .footer-grid>div:not(.footer-brand) a{display:block;font-size:13px;margin:8px 0;color:#c5d2e8}
    .footer-grid a:hover{color:#fff}
    .footer-bottom{border-top:1px solid rgba(255,255,255,.15);margin-top:34px;padding-top:18px;display:flex;justify-content:space-between;gap:20px;font-size:12px;color:#9fb1ce}
    .video-detail-main{padding:46px 0 20px}
    .video-breadcrumb{font-size:13px;color:var(--muted);margin-bottom:20px}
    .video-breadcrumb a{color:var(--primary)}
    .video-layout{display:grid;grid-template-columns:minmax(0,1fr) 300px;gap:28px;align-items:start}
    .video-main-card,.video-side-card{background:#fff;border:1px solid var(--line);border-radius:16px;box-shadow:0 10px 30px rgba(22,40,72,.06)}
    .video-main-card{padding:26px}
    .video-title{font-size:clamp(25px,3vw,38px);line-height:1.3;margin:0 0 15px;color:#10264a}
    .video-meta{display:flex;flex-wrap:wrap;gap:17px;color:var(--muted);font-size:13px;margin-bottom:22px}
    .video-player{background:#0b1424;border-radius:12px;overflow:hidden;min-height:360px;display:flex;align-items:center;justify-content:center;color:#fff}
    .video-player iframe,.video-player video{width:100%;height:100%;min-height:360px;border:0}
    .video-player img{width:100%;height:100%;min-height:360px;object-fit:cover;opacity:.8}
    .player-placeholder{position:absolute}
    .video-intro{margin:28px 0 0;padding:20px;background:#f5f8fd;border-left:4px solid var(--primary);border-radius:0 8px 8px 0;color:#48566b}
    .video-content{margin-top:26px;min-width:0;max-width:100%;overflow-x:auto;color:#334155}
    .video-content img,.video-content table{max-width:100%}
    .video-content table{border-collapse:collapse}
    .video-content td,.video-content th{border:1px solid var(--line);padding:8px}
    .video-tags{display:flex;flex-wrap:wrap;gap:8px;margin-top:26px;padding-top:20px;border-top:1px solid var(--line)}
    .video-tags span{padding:5px 11px;border-radius:20px;background:#edf3fc;color:var(--primary);font-size:12px}
    .video-side-card{padding:20px}
    .video-side-card h2{font-size:18px;margin:0 0 15px;color:#10264a}
    .related-video{display:grid;grid-template-columns:90px 1fr;gap:10px;padding:12px 0;border-bottom:1px solid var(--line)}
    .related-video:last-child{border-bottom:0}
    .related-video img{width:90px;height:60px;border-radius:7px;object-fit:cover;background:#dce5f4}
    .related-video strong{font-size:13px;line-height:1.5;display:block}
    .related-video small{font-size:11px;color:var(--muted)}
    .more-video{display:block;text-align:center;margin-top:15px;border:1px solid var(--primary);color:var(--primary);border-radius:7px;padding:8px;font-size:13px}
    @media(max-width:1050px){
      .header-inner{gap:14px}.logo{min-width:150px}.nav-link{padding:0 8px;font-size:14px}
    }
    @media(max-width:820px){
      .topbar .container{height:auto;min-height:38px;padding-top:7px;padding-bottom:7px;align-items:flex-start;gap:8px}
      .topbar-links{gap:8px;flex-direction:column}
      .main-nav{display:none}.hamburger{display:block}
      .header-btns{margin-left:auto}.member-link{display:none}
      .video-layout{grid-template-columns:1fr}.video-side-card{order:2}
      .footer-grid{grid-template-columns:repeat(2,1fr)}
    }
    @media(max-width:560px){
      .container{width:min(100% - 28px,1180px)}
      .header{height:68px}.logo{font-size:16px}.logo img{width:32px;height:32px}.open-account{padding:7px 10px}
      .video-detail-main{padding-top:28px}.video-main-card{padding:17px}.video-title{font-size:26px}
      .video-player,.video-player iframe,.video-player video,.video-player img{min-height:220px}
      .footer-grid{grid-template-columns:1fr}.footer-bottom{display:block}.footer-bottom span{display:block;margin-top:8px}
    }