:root{
      --theme:#0B3D91;
      --ink:#172033;
      --muted:#667085;
      --line:#e6eaf0;
      --soft:#f5f8fc;
      --accent:#e94f8a;
      --dark:#101827;
      --max:1240px;
    }
    *{box-sizing:border-box}
    html{scroll-behavior:smooth}
    body{margin:0;color:var(--ink);font-family:"Microsoft YaHei","PingFang SC",Arial,sans-serif;background:#fff;line-height:1.7}
    body.drawer-locked{overflow:hidden}
    a{color:inherit;text-decoration:none}
    img{max-width:100%;display:block}
    button{font:inherit}
    .container{width:min(var(--max),calc(100% - 40px));margin:0 auto}

    .topbar{background:#0e1728;color:#d9e2f3;font-size:13px}
    .topbar-inner{min-height:36px;display:flex;align-items:center;justify-content:space-between;gap:20px}
    .topbar-contact{display:flex;gap:22px}
    .topbar a:hover{color:#fff}

    .header{position:relative;z-index:30;background:#fff;border-bottom:1px solid var(--line)}
    .header-inner{min-height:78px;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(--theme)}
    .logo img{width:38px;height:38px;object-fit:contain}
    .main-nav{margin-left:auto}
    .nav-list{display:flex;align-items:stretch;gap:4px;list-style:none;margin:0;padding:0}
    .nav-item{position:relative}
    .nav-link{display:flex;align-items:center;gap:7px;padding:27px 13px;font-size:15px;font-weight:600;white-space:nowrap}
    .nav-link:hover,.nav-link:focus{color:var(--theme)}
    .has-arrow:after{content:"";width:6px;height:6px;border-right:1px solid currentColor;border-bottom:1px solid currentColor;transform:rotate(45deg) translateY(-2px)}
    .dropdown-panel,.mega-menu{position:absolute;top:100%;left:50%;transform:translateX(-50%);visibility:hidden;opacity:0;pointer-events:none;transition:.2s ease;background:#fff;border:1px solid var(--line);box-shadow:0 18px 45px rgba(20,34,60,.15);border-radius:0 0 14px 14px}
    .dropdown-panel{width:280px;padding:14px}
    .dropdown-panel a{display:block;padding:9px 11px;border-radius:8px;font-size:14px}
    .dropdown-panel a:hover{background:var(--soft);color:var(--theme)}
    .dropdown-all,.mega-footer{color:var(--theme)!important;font-weight:700;border-top:1px solid var(--line);margin-top:8px;padding-top:13px!important}
    .mega-menu{width:min(920px,calc(100vw - 40px));padding:22px}
    .nav-item:hover>.dropdown-panel,.nav-item:focus-within>.dropdown-panel,
    .mega-host:hover>.mega-menu,.mega-host:focus-within>.mega-menu{visibility:visible;opacity:1;pointer-events:auto}
    .nav-item:hover>.dropdown-panel:before,.mega-host:hover>.mega-menu:before{content:"";position:absolute;left:0;right:0;top:-15px;height:15px}
    .mega-title{margin:0 0 13px;color:var(--theme);font-weight:800;font-size:14px}
    .mega-grid{display:grid;gap:12px}
    .mega-grid-6{grid-template-columns:repeat(3,1fr)}
    .mega-grid-3{grid-template-columns:repeat(3,1fr)}
    .mega-card{display:flex;gap:10px;align-items:flex-start;padding:11px;border:1px solid var(--line);border-radius:10px;transition:.2s}
    .mega-card:hover{border-color:#a9bddf;transform:translateY(-2px)}
    .mega-card>img{width:42px;height:42px;object-fit:cover;border-radius:8px;background:#eef3fa;flex:none}
    .mega-card span{min-width:0}
    .mega-card strong,.mega-card small{display:block;overflow:hidden;text-overflow:ellipsis}
    .mega-card strong{font-size:13px;white-space:nowrap}
    .mega-card small{font-size:11px;color:var(--muted);line-height:1.5}
    .mega-split{display:grid;grid-template-columns:180px 1fr;gap:22px}
    .mega-categories{display:grid;gap:6px}
    .mega-categories a{padding:7px 9px;border-radius:7px;font-size:13px}
    .mega-categories a:hover{background:var(--soft);color:var(--theme)}
    .mega-video-card>img{width:72px;height:48px}
    .header-btns{display:flex;align-items:center;gap:12px}
    .header-account{font-size:13px;color:var(--theme);font-weight:700}
    .header-open{padding:8px 16px;border-radius:20px;background:var(--theme);color:#fff;font-size:13px;font-weight:700}
    .hamburger{display:none;width:42px;height:40px;border:1px solid var(--line);border-radius:8px;background:#fff;padding:9px}
    .hamburger span{display:block;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(5,13,29,.56);opacity:0;visibility:hidden;transition:.25s;z-index:80}
    .drawer-overlay.open{opacity:1;visibility:visible}
    .mobile-drawer{position:fixed;top:0;right:0;width:min(390px,88vw);height:100vh;background:#fff;transform:translateX(100%);transition:.3s;z-index:90;overflow:auto}
    .mobile-drawer.open{transform:translateX(0)}
    .drawer-head{display:flex;align-items:center;gap:15px;padding:20px;border-bottom:1px solid var(--line);color:var(--theme);font-weight:800}
    .drawer-head>a{margin-left:auto;padding:5px 13px;border-radius:18px;background:var(--theme);color:#fff;font-size:13px}
    .drawer-close{border:0;background:transparent;font-size:28px;line-height:1;color:var(--muted);cursor:pointer}
    .drawer-menu{padding:10px 20px 30px}
    .drawer-link,.drawer-toggle{display:block;width:100%;padding:13px 0;border:0;border-bottom:1px solid var(--line);background:transparent;text-align:left;font-weight:700;color:var(--ink);cursor:pointer}
    .drawer-toggle:after{content:"+";float:right;color:var(--theme);font-size:20px}
    .drawer-toggle.active:after{content:"−"}
    .drawer-submenu{display:none;padding:5px 0 8px 15px}
    .drawer-submenu.open{display:block}
    .drawer-submenu a{display:block;padding:7px 0;color:var(--muted);font-size:14px}

    .download-page-main{background:linear-gradient(180deg,#f5f8fc 0,#fff 520px);padding-bottom:90px}
    .download-hero{padding:76px 0 54px;text-align:center}
    .eyebrow{display:inline-flex;align-items:center;gap:8px;color:var(--theme);font-size:13px;font-weight:800;letter-spacing:.12em}
    .eyebrow:before{content:"";width:28px;height:2px;background:var(--accent)}
    .download-hero h1{margin:12px 0 12px;font-size:clamp(34px,5vw,64px);line-height:1.16;letter-spacing:-.04em}
    .download-hero p{max-width:680px;margin:0 auto;color:var(--muted);font-size:17px}
    .download-actions{margin-top:28px;display:flex;justify-content:center;gap:12px;flex-wrap:wrap}
    .primary-btn,.secondary-btn{display:inline-flex;align-items:center;justify-content:center;min-height:46px;padding:0 24px;border-radius:8px;font-weight:700}
    .primary-btn{background:var(--theme);color:#fff;box-shadow:0 10px 22px rgba(11,61,145,.2)}
    .secondary-btn{border:1px solid #cbd6e5;color:var(--theme);background:#fff}
    .download-panel{padding:28px;border:1px solid #dce5f1;border-radius:20px;background:#fff;box-shadow:0 18px 50px rgba(28,53,91,.08)}
    .platform-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:18px}
    .platform-card{padding:25px;border-radius:14px;background:linear-gradient(145deg,#f8fbff,#eef4fc);border:1px solid #e2eaf5}
    .platform-icon{width:48px;height:48px;display:grid;place-items:center;border-radius:12px;background:var(--theme);color:#fff;font-weight:800;font-size:20px}
    .platform-card h2{margin:16px 0 5px;font-size:20px}
    .platform-card p{margin:0 0 18px;color:var(--muted);font-size:14px}
    .platform-card a{display:inline-block;color:var(--theme);font-weight:800;font-size:14px}
    .download-section{padding-top:64px}
    .section-heading{text-align:center;margin-bottom:28px}
    .section-heading h2{margin:0 0 8px;font-size:30px}
    .section-heading p{margin:0;color:var(--muted)}
    .steps{display:grid;grid-template-columns:repeat(4,1fr);gap:18px}
    .step{position:relative;padding:24px;background:#fff;border:1px solid var(--line);border-radius:14px}
    .step-number{color:var(--accent);font-size:28px;font-weight:900}
    .step h3{margin:8px 0 6px;font-size:17px}
    .step p{margin:0;color:var(--muted);font-size:14px}
    .faq-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:14px}
    .faq-item{padding:20px 22px;border:1px solid var(--line);border-radius:12px;background:#fff}
    .faq-item h3{margin:0 0 7px;font-size:16px}
    .faq-item p{margin:0;color:var(--muted);font-size:14px}
    .download-notice{margin-top:30px;padding:18px 22px;border-left:4px solid var(--accent);background:#fff5f8;color:#6e3b4e;font-size:14px}

    .footer{background:#101827;color:#c7d2e3;padding:58px 0 22px}
    .footer-main{display:grid;grid-template-columns:1.5fr 1fr 1fr 1fr;gap:38px}
    .footer .logo{color:#fff}
    .footer-brand p{max-width:350px;color:#9eacc0;font-size:14px}
    .footer-search{display:inline-block;color:#8fc0ff;font-size:13px}
    .footer h3{margin:5px 0 15px;color:#fff;font-size:15px}
    .footer-links{display:grid;gap:8px;font-size:13px}
    .footer-links a:hover,.footer-contact a:hover{color:#fff}
    .footer-contact{display:grid;gap:8px;font-size:13px}
    .footer-bottom{display:flex;justify-content:space-between;gap:20px;margin-top:42px;padding-top:18px;border-top:1px solid rgba(255,255,255,.12);color:#8291a7;font-size:12px}
    .risk-note{max-width:650px;text-align:right}

    @media (max-width:1080px){
      .main-nav{display:none}
      .header-btns{margin-left:auto}
      .hamburger{display:block}
      .platform-grid{grid-template-columns:repeat(3,1fr)}
    }
    @media (max-width:760px){
      .container{width:min(var(--max),calc(100% - 28px))}
      .topbar-inner{padding:8px 0;align-items:flex-start;flex-direction:column;gap:2px}
      .topbar-contact{gap:12px;flex-wrap:wrap}
      .header-inner{min-height:68px;gap:12px}
      .header-account{display:none}
      .header-open{padding:7px 12px}
      .download-hero{padding:52px 0 38px}
      .download-hero p{font-size:15px}
      .download-panel{padding:16px}
      .platform-grid,.steps,.faq-grid{grid-template-columns:1fr}
      .download-section{padding-top:46px}
      .section-heading h2{font-size:25px}
      .footer-main{grid-template-columns:1fr 1fr;gap:28px 20px}
      .footer-brand{grid-column:1/-1}
      .footer-bottom{display:block}
      .risk-note{margin-top:10px;text-align:left}
    }
    @media (max-width:430px){
      .footer-main{grid-template-columns:1fr}
      .footer-brand{grid-column:auto}
      .header-open{font-size:12px}
    }