:root{
      --theme:#0B3D91;
      --theme-dark:#082c69;
      --ink:#172238;
      --muted:#68758a;
      --line:#dce4ef;
      --soft:#f4f7fb;
      --white:#fff;
      --shadow:0 18px 50px rgba(13,43,86,.10);
      --radius:18px;
    }
    *{box-sizing:border-box}
    html{scroll-behavior:smooth}
    body{margin:0;color:var(--ink);background:#fff;font-family:"PingFang SC","Microsoft YaHei",Arial,sans-serif;line-height:1.7}
    a{color:inherit;text-decoration:none}
    img{max-width:100%;height:auto}
    .container{width:min(1180px,calc(100% - 40px));margin:0 auto}
    .topbar{background:#0c1d3b;color:#dfe8f7;font-size:13px}
    .topbar .container{min-height:36px;display:flex;align-items:center;justify-content:space-between;gap:20px}
    .topbar a{margin-left:18px;color:#fff}
    .header{position:relative;z-index:20;background:#fff;border-bottom:1px solid var(--line)}
    .header-inner{min-height:78px;display:flex;align-items:center;gap:30px}
    .logo{display:flex;align-items:center;gap:10px;white-space:nowrap;font-weight:800;font-size:19px;color:var(--theme)}
    .logo img{width:38px;height:38px;object-fit:contain}
    .main-nav{margin-left:auto}
    .nav-list{display:flex;align-items:center;gap:4px;margin:0;padding:0;list-style:none}
    .nav-item{position:relative}
    .nav-link{display:flex;align-items:center;gap:5px;padding:27px 13px;font-size:15px;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:calc(100% + 1px);left:50%;transform:translateX(-50%);display:none;background:#fff;border:1px solid var(--line);border-radius:0 0 16px 16px;box-shadow:var(--shadow);padding:18px;z-index:30}
    .dropdown-panel{width:240px}
    .dropdown-panel a{display:block;padding:9px 10px;border-bottom:1px solid #edf1f6;font-size:14px}
    .mega-menu{width:650px}
    .nav-item:hover>.dropdown-panel,.nav-item:focus-within>.dropdown-panel,
    .nav-item:hover>.mega-menu,.nav-item:focus-within>.mega-menu{display:block}
    .mega-menu:before{content:"";position:absolute;left:0;right:0;top:-12px;height:12px}
    .mega-title{font-size:14px;font-weight:800;color:var(--theme);margin:2px 0 10px}
    .mega-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:10px;margin-bottom:15px}
    .mega-card{display:flex;flex-direction:column;gap:3px;min-height:82px;padding:11px;border:1px solid var(--line);border-radius:12px;background:#fbfcfe}
    .mega-card:hover{border-color:var(--theme);background:#f2f6fc}
    .mega-card img{width:30px;height:30px;object-fit:contain}
    .mega-card strong{font-size:13px}
    .mega-card small{font-size:11px;color:var(--muted);line-height:1.45}
    .mega-footer{display:block;padding-top:10px;border-top:1px solid var(--line);color:var(--theme);font-weight:700;font-size:13px}
    .header-btns{display:flex;align-items:center;gap:9px}
    .member-btn,.open-btn{padding:9px 13px;border-radius:9px;font-size:13px}
    .member-btn{color:var(--theme);border:1px solid #c9d6ea}
    .open-btn{color:#fff;background:var(--theme)}
    .hamburger{display:none;border:0;background:transparent;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;background:rgba(4,17,39,.48);opacity:0;visibility:hidden;transition:.25s;z-index:50}
    .drawer-overlay.open{opacity:1;visibility:visible}
    .mobile-drawer{position:fixed;top:0;right:0;width:min(390px,88vw);height:100vh;overflow:auto;background:#fff;transform:translateX(100%);transition:.3s;z-index:51;box-shadow:-15px 0 40px rgba(0,0,0,.15)}
    .mobile-drawer.open{transform:translateX(0)}
    .drawer-head{display:flex;align-items:center;gap:15px;padding:20px;border-bottom:1px solid var(--line);font-weight:800}
    .drawer-head>a{margin-left:auto;color:var(--theme)}
    .drawer-close{border:0;background:transparent;font-size:28px;line-height:1;cursor:pointer}
    .drawer-menu{padding:12px 20px 30px}
    .drawer-link,.drawer-toggle{display:block;width:100%;padding:13px 0;border:0;border-bottom:1px solid #edf0f5;background:transparent;text-align:left;font-size:15px;color:var(--ink);cursor:pointer}
    .drawer-toggle:after{content:"+";float:right;color:var(--muted);font-size:19px}
    .drawer-toggle.active:after{content:"−"}
    .drawer-submenu{display:none;padding:4px 0 7px 15px}
    .drawer-submenu.open{display:block}
    .drawer-submenu a{display:block;padding:8px 0;color:var(--muted);font-size:14px}
    .footer{margin-top:70px;background:#0c1d3b;color:#cdd8ea}
    .footer-grid{display:grid;grid-template-columns:1.5fr 1fr 1fr 1.2fr;gap:35px;padding:48px 0 38px}
    .footer h3{margin:0 0 14px;color:#fff;font-size:15px}
    .footer p{margin:7px 0;font-size:13px}
    .footer-brand strong{display:block;margin-bottom:14px;color:#fff;font-size:20px}
    .footer-grid>div>a{display:block;margin:8px 0;font-size:13px}
    .footer-grid>div>a:hover{color:#fff}
    .footer-bottom{padding:18px 0;border-top:1px solid rgba(255,255,255,.14);font-size:12px;color:#aebbd0}
    .tool-detail-page{padding:54px 0 10px;background:linear-gradient(180deg,#f7faff 0,#fff 420px)}
    .breadcrumb{display:flex;gap:8px;align-items:center;color:var(--muted);font-size:13px;margin-bottom:25px}
    .breadcrumb a{color:var(--theme)}
    .tool-layout{display:grid;grid-template-columns:minmax(0,1fr) 310px;gap:28px;align-items:start}
    .tool-main,.tool-side{background:#fff;border:1px solid var(--line);border-radius:var(--radius);box-shadow:0 12px 35px rgba(20,54,100,.06)}
    .tool-main{padding:34px}
    .tool-heading{display:flex;gap:20px;align-items:center;padding-bottom:25px;border-bottom:1px solid var(--line)}
    .tool-icon{width:76px;height:76px;object-fit:contain;border-radius:16px;background:#eff4fb;padding:12px}
    .tool-heading h1{margin:0 0 8px;font-size:clamp(25px,4vw,38px);line-height:1.25;color:#102653}
    .tool-intro{margin:0;color:var(--muted);font-size:15px}
    .tool-meta{display:flex;flex-wrap:wrap;gap:18px;margin:20px 0;padding:15px 18px;background:var(--soft);border-radius:12px;color:var(--muted);font-size:13px}
    .tool-meta strong{color:var(--ink);margin-left:4px}
    .tool-content{min-width:0;max-width:100%;overflow-x:auto;padding-top:12px;font-size:16px}
    .tool-content img,.tool-content table{max-width:100%}
    .tool-content h2,.tool-content h3{color:#102653;margin-top:28px}
    .tool-content a{color:var(--theme);text-decoration:underline}
    .tool-content pre{max-width:100%;overflow:auto;padding:18px;background:#0d1d36;color:#d9e6ff;border-radius:10px}
    .tool-content blockquote{margin:20px 0;padding:12px 18px;border-left:4px solid var(--theme);background:#f2f6fc;color:#53647c}
    .tool-side{padding:23px;position:sticky;top:20px}
    .tool-side h2{margin:0 0 17px;font-size:19px;color:#102653}
    .related-tool{display:flex;gap:12px;padding:13px 0;border-bottom:1px solid #edf1f6}
    .related-tool:last-child{border-bottom:0}
    .related-tool img{width:42px;height:42px;object-fit:contain;border-radius:9px;background:#eff4fb;padding:7px;flex:0 0 auto}
    .related-tool strong{display:block;font-size:14px;margin-bottom:3px}
    .related-tool span{display:block;color:var(--muted);font-size:12px;line-height:1.45}
    .tool-side-link{display:block;margin-top:18px;padding:11px;text-align:center;border-radius:9px;background:var(--theme);color:#fff;font-size:14px}
    @media(max-width:1050px){
      .main-nav{display:none}
      .hamburger{display:block}
      .header-btns{margin-left:auto}
      .tool-layout{grid-template-columns:minmax(0,1fr) 270px}
    }
    @media(max-width:760px){
      .container{width:min(100% - 28px,620px)}
      .topbar .container{padding:8px 0;display:block;font-size:11px}
      .topbar .container>span{display:block}
      .topbar a{margin-left:12px}
      .header-inner{min-height:68px;gap:10px}
      .logo{font-size:16px}
      .logo img{width:32px;height:32px}
      .member-btn{display:none}
      .open-btn{font-size:12px;padding:8px 10px}
      .tool-detail-page{padding-top:30px}
      .tool-layout{display:block}
      .tool-main{padding:22px 18px}
      .tool-side{position:static;margin-top:20px}
      .tool-heading{align-items:flex-start;gap:14px}
      .tool-icon{width:58px;height:58px}
      .tool-heading h1{font-size:25px}
      .tool-meta{gap:10px;display:block}
      .tool-meta span{display:block;margin:4px 0}
      .footer-grid{grid-template-columns:1fr 1fr;gap:25px;padding:35px 0}
      .footer-brand{grid-column:1/-1}
      .mega-menu,.dropdown-panel{display:none!important}
    }
    @media(max-width:430px){
      .footer-grid{grid-template-columns:1fr}
      .footer-brand{grid-column:auto}
    }