:root{--theme:#0B3D91;--ink:#172033;--muted:#6d7890;--line:#e7ebf2;--soft:#f4f7fb;--white:#fff}
    *{box-sizing:border-box}html,body{margin:0;padding:0;color:var(--ink);font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","Microsoft YaHei",Arial,sans-serif;background:#f7f9fc}a{color:inherit;text-decoration:none}button{font:inherit}.container{width:min(1180px,calc(100% - 40px));margin:auto}
    .topbar{height:38px;background:#f0f3f8;color:#657086;font-size:13px}.topbar .container{height:100%;display:flex;align-items:center;justify-content:space-between}.topbar-links{display:flex;gap:22px}.topbar a:hover{color:var(--theme)}
    .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:42px}.logo{display:flex;align-items:center;gap:10px;white-space:nowrap;font-size:19px;font-weight:800;color:var(--theme)}.logo img{width:34px;height:34px;object-fit:contain}.main-nav{margin-left:auto}.nav-list{list-style:none;margin:0;padding:0;display:flex;align-items:stretch;gap:4px}.nav-item{position:relative}.nav-link{display:block;padding:29px 15px 28px;font-size:14px;white-space:nowrap}.nav-link:hover,.nav-link:focus{color:var(--theme)}.has-arrow:after{content:"⌄";margin-left:6px;font-size:12px}.dropdown-panel,.mega-menu{position:absolute;top:calc(100% + 1px);left:50%;transform:translateX(-50%);width:300px;background:#fff;border:1px solid var(--line);border-radius:0 0 12px 12px;box-shadow:0 15px 35px #18345b1b;padding:18px;display:none}.nav-item:hover>.dropdown-panel,.nav-item:focus-within>.dropdown-panel,.nav-item:hover>.mega-menu,.nav-item:focus-within>.mega-menu{display:block}.dropdown-panel:before,.mega-menu:before{content:"";position:absolute;left:0;right:0;top:-10px;height:10px}.dropdown-panel a{display:block;padding:10px 4px;border-bottom:1px solid var(--line);font-size:13px}.dropdown-panel a:last-child{color:var(--theme);border:0}.mega-menu{width:620px}.mega-title{margin:0 0 12px;font-weight:800;font-size:14px;color:var(--theme)}.mega-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:9px}.mega-card{display:block;padding:12px;background:var(--soft);border-radius:8px;font-size:12px;line-height:1.6}.mega-card:hover{background:#e8f0ff;color:var(--theme)}.mega-card img{width:23px;height:23px;object-fit:contain;vertical-align:middle;margin-right:5px}.mega-card strong{font-size:13px}.mega-footer{display:block;text-align:center;margin-top:15px;color:var(--theme);font-size:13px;font-weight:700}
    .header-btns{display:flex;align-items:center;gap:10px}.member-btn,.account-btn{font-size:13px;border-radius:6px;padding:9px 13px}.member-btn{color:var(--theme);border:1px solid #cbd8ef}.account-btn{background:var(--theme);color:#fff}.hamburger{display:none;width:40px;height:38px;border:1px solid var(--line);background:#fff;border-radius:7px;padding:8px}.hamburger span{display:block;height:2px;background:var(--theme);margin:4px 0;border-radius:2px}
    .drawer-overlay{display:none;position:fixed;inset:0;background:#0d1b3080;z-index:40}.drawer-overlay.open{display:block}.mobile-drawer{position:fixed;right:0;top:0;bottom:0;width:min(360px,88vw);background:#fff;z-index:50;transform:translateX(100%);transition:.25s;overflow:auto}.mobile-drawer.open{transform:translateX(0)}.drawer-head{height:70px;padding:18px 20px;display:flex;align-items:center;gap:14px;border-bottom:1px solid var(--line);font-weight:700}.drawer-head>a{margin-left:auto;color:var(--theme);font-size:13px}.drawer-close{border:0;background:none;font-size:28px;color:#637087}.drawer-menu{padding:12px 20px}.drawer-link,.drawer-toggle{display:block;width:100%;text-align:left;padding:14px 0;border:0;border-bottom:1px solid var(--line);background:none;font-size:15px;color:var(--ink)}.drawer-toggle:after{content:"＋";float:right;color:var(--theme)}.drawer-toggle.active:after{content:"－"}.drawer-submenu{display:none;padding:4px 0 8px 15px}.drawer-submenu.open{display:block}.drawer-submenu a{display:block;padding:9px 0;color:var(--muted);font-size:13px}
    .video-detail-main{padding:46px 0 72px}.video-breadcrumb{font-size:13px;color:var(--muted);margin-bottom:22px}.video-breadcrumb a{color:var(--theme)}.video-detail-main h1{font-size:clamp(28px,4vw,46px);line-height:1.2;margin:0 0 18px;letter-spacing:-.03em}.video-meta{display:flex;flex-wrap:wrap;gap:16px;color:var(--muted);font-size:14px;margin-bottom:28px}.video-stage{background:#101827;border-radius:16px;overflow:hidden;box-shadow:0 18px 45px #1525441c}.video-player{min-height:440px;display:flex;align-items:center;justify-content:center;background:linear-gradient(135deg,#152a4a,#07101e);position:relative}.video-player img{width:100%;height:440px;object-fit:cover;opacity:.6}.video-play{position:absolute;width:76px;height:76px;border:0;border-radius:50%;background:#fff;color:var(--theme);font-size:28px;padding-left:6px;box-shadow:0 8px 25px #0006}.video-caption{padding:16px 22px;color:#dce7f8;font-size:14px}.video-content-grid{display:grid;grid-template-columns:minmax(0,1fr) 300px;gap:26px;margin-top:28px}.video-article,.related-videos{background:#fff;border:1px solid var(--line);border-radius:14px;padding:26px}.video-article h2,.related-videos h2{font-size:20px;margin:0 0 18px}.video-body{min-width:0;max-width:100%;overflow-x:auto;line-height:1.9;font-size:15px}.video-body img,.video-body table{max-width:100%}.video-tags{display:flex;flex-wrap:wrap;gap:8px;margin-top:24px}.video-tags span{background:#edf3ff;color:var(--theme);padding:5px 10px;border-radius:20px;font-size:12px}.related-list{display:grid;gap:14px}.related-item{display:grid;grid-template-columns:92px 1fr;gap:10px;padding-bottom:14px;border-bottom:1px solid var(--line)}.related-item:last-child{border:0;padding-bottom:0}.related-item img{width:92px;height:62px;object-fit:cover;border-radius:7px;background:#e9eef6}.related-item strong{display:block;font-size:13px;line-height:1.5}.related-item small{display:block;color:var(--muted);font-size:12px;margin-top:6px}.video-actions{display:flex;gap:12px;margin-top:24px}.video-actions a{padding:11px 18px;border-radius:7px;background:var(--theme);color:#fff;font-size:13px}.video-actions a.secondary{background:#eef3fb;color:var(--theme)}
    .footer{background:#101a2b;color:#c3cede;padding:48px 0 20px}.footer-grid{display:grid;grid-template-columns:1.4fr 1fr 1fr 1.2fr;gap:35px}.footer h3,.footer h4{margin:0 0 16px;color:#fff}.footer h3{font-size:20px}.footer h4{font-size:14px}.footer p{font-size:13px;line-height:1.8;margin:7px 0}.footer-grid>div>a{display:block;font-size:13px;margin:9px 0;color:#c3cede}.footer-grid>div>a:hover{color:#fff}.footer-bottom{display:flex;justify-content:space-between;gap:20px;border-top:1px solid #2b384c;margin-top:32px;padding-top:18px;font-size:12px;color:#8e9bb0}
    @media(max-width:980px){.main-nav{display:none}.header-btns{margin-left:auto}.hamburger{display:block}.member-btn{display:none}.mega-menu{position:static;transform:none}.video-content-grid{grid-template-columns:1fr}.footer-grid{grid-template-columns:repeat(2,1fr)}}
    @media(max-width:600px){.container{width:min(100% - 28px,1180px)}.topbar{height:auto;padding:9px 0}.topbar .container{align-items:flex-start;gap:6px;flex-direction:column}.topbar-links{gap:12px;flex-wrap:wrap}.header{height:66px}.nav-link{padding:22px 10px}.video-detail-main{padding:30px 0 48px}.video-player,.video-player img{height:230px;min-height:230px}.video-article,.related-videos{padding:20px}.footer-grid{grid-template-columns:1fr}.footer-bottom{display:block;line-height:1.8}.footer-bottom span{display:block;margin-top:5px}}