:root{
      --theme:#0B3D91;
      --ink:#172033;
      --muted:#667085;
      --line:#e6eaf0;
      --soft:#f5f7fb;
      --gold:#d89b32;
      --dark:#111827;
      --white:#fff;
    }
    *{box-sizing:border-box}
    html{scroll-behavior:smooth}
    body{margin:0;color:var(--ink);font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","Microsoft YaHei",Arial,sans-serif;background:#fff;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:#101827;color:#d8deea;font-size:13px}
    .topbar .container{min-height:36px;display:flex;align-items:center;justify-content:space-between;gap:16px}
    .topbar a{margin-left:20px;color:#f1f4f8}
    .header{position:relative;z-index:20;background:#fff;border-bottom:1px solid var(--line)}
    .header-inner{min-height:76px;display:flex;align-items:center;gap:30px}
    .logo{display:flex;align-items:center;gap:10px;color:var(--theme);font-weight:800;font-size:19px;white-space:nowrap}
    .logo img{width:34px;height:34px;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;min-height:76px;padding:0 14px;font-size:15px;white-space:nowrap}
    .nav-link:hover,.nav-link:focus{color:var(--theme)}
    .has-arrow:after{content:"⌄";font-size:13px;margin-left:6px;color:#8993a4}
    .dropdown-panel,.mega-menu{position:absolute;top:calc(100% + 1px);left:50%;transform:translateX(-50%);width:270px;padding:18px;background:#fff;border:1px solid var(--line);border-radius:0 0 14px 14px;box-shadow:0 16px 40px rgba(17,24,39,.12);opacity:0;visibility:hidden;transition:.2s;z-index:30}
    .mega-menu{width:620px}
    .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}
    .dropdown-panel:before,.mega-menu:before{content:"";position:absolute;left:0;right:0;top:-12px;height:12px}
    .dropdown-panel>a,.mega-grid>a{display:block;padding:8px 10px;border-radius:8px;font-size:14px}
    .dropdown-panel>a:hover,.mega-grid>a:hover{background:#f1f5fb;color:var(--theme)}
    .mega-title{margin:0 0 10px;color:var(--theme);font-weight:800;font-size:14px}
    .mega-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:5px}
    .mega-grid small{display:block;color:var(--muted);font-size:12px;line-height:1.5}
    .mega-grid strong{display:block;font-size:14px}
    .product-mini{display:grid!important;grid-template-columns:30px 1fr;column-gap:8px;align-items:center}
    .product-mini img{width:28px;height:28px;object-fit:contain;grid-row:span 2}
    .mega-footer{display:block!important;margin-top:13px;padding-top:12px!important;border-top:1px solid var(--line);color:var(--theme);font-weight:700}
    .header-btns{display:flex;align-items:center;gap:10px;white-space:nowrap}
    .member-btn{font-size:14px;color:var(--theme)}
    .open-btn{padding:8px 15px;background:var(--theme);color:#fff;border-radius:7px;font-size:14px}
    .hamburger{display:none;width:42px;height:40px;border:1px solid var(--line);background:#fff;border-radius:8px;padding:8px;cursor:pointer}
    .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(8,15,28,.5);opacity:0;visibility:hidden;transition:.2s;z-index:50}
    .drawer-overlay.open{opacity:1;visibility:visible}
    .mobile-drawer{position:fixed;top:0;right:-360px;width:min(360px,88vw);height:100vh;overflow:auto;background:#fff;z-index:51;transition:.25s;box-shadow:-12px 0 35px rgba(0,0,0,.15)}
    .mobile-drawer.open{right:0}
    .drawer-head{display:flex;align-items:center;gap:12px;padding:20px;border-bottom:1px solid var(--line)}
    .drawer-head strong{margin-right:auto;color:var(--theme)}
    .drawer-head a{padding:5px 12px;background:var(--theme);color:#fff;border-radius:5px;font-size:13px}
    .drawer-close{border:0;background:none;font-size:28px;line-height:1;cursor:pointer;color:#667085}
    .drawer-menu{padding:12px 20px 30px}
    .drawer-link,.drawer-toggle{display:block;width:100%;padding:13px 0;border:0;border-bottom:1px solid var(--line);background:none;text-align:left;color:var(--ink);font-size:15px;cursor:pointer}
    .drawer-toggle:after{content:"+";float:right;color:#98a2b3}
    .drawer-toggle.active:after{content:"−"}
    .drawer-submenu{max-height:0;overflow:hidden;padding-left:14px;transition:.2s}
    .drawer-submenu.open{max-height:600px}
    .drawer-submenu a{display:block;padding:8px 0;color:var(--muted);font-size:14px}
    .footer{margin-top:80px;background:#101827;color:#c8d0dc}
    .footer-grid{display:grid;grid-template-columns:1.5fr 1fr 1fr 1.2fr;gap:38px;padding:48px 0 36px}
    .footer h3{margin:0 0 14px;color:#fff;font-size:15px}
    .footer p{margin:6px 0;font-size:13px}
    .footer-grid>div>a{display:block;margin:7px 0;color:#c8d0dc;font-size:13px}
    .footer-brand strong{color:#fff;font-size:20px}
    .footer-bottom{padding:18px 0;border-top:1px solid rgba(255,255,255,.12);font-size:12px;color:#99a5b7}
    .download-page-main{background:linear-gradient(180deg,#f8faff 0,#fff 500px)}
    .download-hero{padding:72px 0 62px;text-align:center;background:radial-gradient(circle at 50% 0,#dfeaff 0,transparent 55%)}
    .eyebrow{display:inline-flex;padding:5px 13px;border-radius:999px;background:#e8f0ff;color:var(--theme);font-size:13px;font-weight:700}
    .download-hero h1{max-width:780px;margin:18px auto 12px;font-size:clamp(32px,5vw,56px);line-height:1.18;letter-spacing:-1px;color:#13213a}
    .download-hero p{max-width:650px;margin:0 auto;color:var(--muted);font-size:17px}
    .download-actions{display:flex;justify-content:center;gap:12px;flex-wrap:wrap;margin-top:28px}
    .primary-btn,.secondary-btn{display:inline-flex;align-items:center;justify-content:center;border-radius:8px;padding:12px 22px;font-weight:700}
    .primary-btn{background:var(--theme);color:#fff;box-shadow:0 8px 20px rgba(11,61,145,.2)}
    .secondary-btn{border:1px solid #cfd7e5;background:#fff;color:var(--theme)}
    .download-wrap{padding:18px 0}
    .download-section{padding:52px 0}
    .section-heading{text-align:center;max-width:680px;margin:0 auto 30px}
    .section-heading h2{margin:0 0 8px;font-size:30px;color:#18243a}
    .section-heading p{margin:0;color:var(--muted)}
    .steps{display:grid;grid-template-columns:repeat(3,1fr);gap:20px}
    .step-card{position:relative;padding:28px 24px;background:#fff;border:1px solid var(--line);border-radius:15px;box-shadow:0 10px 30px rgba(26,48,87,.06)}
    .step-num{display:flex;align-items:center;justify-content:center;width:42px;height:42px;border-radius:50%;background:var(--theme);color:#fff;font-weight:800;font-size:18px}
    .step-card h3{margin:18px 0 7px;font-size:19px}
    .step-card p{margin:0;color:var(--muted);font-size:14px}
    .platform-panel{display:grid;grid-template-columns:1.1fr .9fr;gap:28px;align-items:stretch;padding:30px;background:#101827;border-radius:20px;color:#fff}
    .platform-copy h2{margin:0 0 12px;font-size:28px}
    .platform-copy p{margin:0;color:#bdc8d9}
    .platform-list{display:grid;grid-template-columns:repeat(2,1fr);gap:12px;margin-top:24px}
    .platform-list div{padding:15px;border:1px solid rgba(255,255,255,.15);border-radius:10px;background:rgba(255,255,255,.05)}
    .platform-list strong{display:block}
    .platform-list span{font-size:12px;color:#aebbd0}
    .checklist{margin:20px 0 0;padding:0;list-style:none;color:#d8e0eb}
    .checklist li{margin:7px 0}
    .checklist li:before{content:"✓";margin-right:8px;color:#77b4ff;font-weight:800}
    .security-card{display:flex;flex-direction:column;justify-content:center;padding:24px;border-radius:15px;background:linear-gradient(145deg,#174b9c,#0b3d91)}
    .security-card .shield{font-size:42px;margin-bottom:12px}
    .security-card h3{margin:0 0 8px;font-size:20px}
    .security-card p{margin:0;color:#d9e7ff;font-size:14px}
    .faq-list{max-width:820px;margin:auto;border-top:1px solid var(--line)}
    .faq-item{padding:18px 0;border-bottom:1px solid var(--line)}
    .faq-item h3{margin:0 0 6px;font-size:17px}
    .faq-item p{margin:0;color:var(--muted);font-size:14px}
    .notice{padding:18px 20px;border-left:4px solid var(--gold);background:#fff8e9;color:#76551d;border-radius:8px;font-size:13px}
    @media(max-width:1050px){
      .main-nav{display:none}
      .hamburger{display:block}
      .header-btns{margin-left:auto}
      .footer-grid{grid-template-columns:repeat(2,1fr)}
      .platform-panel{grid-template-columns:1fr}
    }
    @media(max-width:680px){
      .container{width:min(100% - 28px,1180px)}
      .topbar .container{display:block;padding:8px 0}
      .topbar .container>span{display:block}
      .topbar a{margin:0 14px 0 0}
      .header-inner{min-height:66px}
      .logo{font-size:16px}
      .member-btn{display:none}
      .download-hero{padding:48px 0 42px}
      .download-hero h1{font-size:35px}
      .download-hero p{font-size:15px}
      .steps{grid-template-columns:1fr}
      .download-section{padding:36px 0}
      .section-heading h2{font-size:26px}
      .platform-panel{padding:22px}
      .platform-list{grid-template-columns:1fr}
      .footer{margin-top:45px}
      .footer-grid{grid-template-columns:1fr;gap:22px;padding:34px 0 26px}
    }