:root{--blue:#0B3D91;--ink:#172033;--muted:#667085;--line:#e5eaf1;--bg:#f6f8fb;--white:#fff;--accent:#d99a32}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;color:var(--ink);background:var(--bg);font-family:"Microsoft YaHei","PingFang SC",Arial,sans-serif;line-height:1.6}
a{color:inherit;text-decoration:none}
img{max-width:100%;display:block}
.container{width:min(1180px,calc(100% - 40px));margin:0 auto}
.topbar{background:#101b31;color:#cbd5e1;font-size:13px}
.topbar-inner{height:38px;display:flex;align-items:center;justify-content:space-between}
.topbar a{color:#e7edf8}.topbar-contact{display:flex;gap:10px}
.header{position:relative;z-index:30;background:#fff;border-bottom:1px solid var(--line)}
.header-inner{height:78px;display:flex;align-items:center;gap:30px}
.logo{display:flex;align-items:center;gap:10px;white-space:nowrap;font-size:20px;font-weight:800;color:var(--blue)}
.logo img{width:36px;height:36px;object-fit:contain}
.main-nav{flex:1}
.nav-list{display:flex;justify-content:center;align-items:stretch;gap:4px;list-style:none;margin:0;padding:0}
.nav-item{position:relative}
.nav-link{display:flex;align-items:center;height:78px;padding:0 14px;font-size:15px;color:#263449;white-space:nowrap}
.nav-link:hover,.nav-link:focus-within{color:var(--blue)}
.has-arrow:after{content:"";width:6px;height:6px;margin-left:8px;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;background:#fff;border:1px solid var(--line);box-shadow:0 18px 45px rgba(18,34,61,.14);transition:.2s;z-index:50}
.dropdown-panel{width:270px;padding:20px}
.mega-menu{width:680px;padding:24px}
.nav-item:after{content:"";position:absolute;left:0;right:0;top:100%;height:12px}
.nav-item:hover>.dropdown-panel,.nav-item:focus-within>.dropdown-panel,.nav-item:hover>.mega-menu,.nav-item:focus-within>.mega-menu{visibility:visible;opacity:1;pointer-events:auto}
.dropdown-title,.mega-title{margin:0 0 13px;font-size:14px;font-weight:800;color:var(--blue)}
.dropdown-articles{display:grid;gap:9px;font-size:14px}
.dropdown-articles a:hover,.mega-categories a:hover{color:var(--blue)}
.dropdown-more,.mega-footer{display:block;margin-top:16px;padding-top:13px;border-top:1px solid var(--line);font-size:13px;color:var(--blue);font-weight:700}
.mega-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:12px}
.mega-card{display:block;border:1px solid var(--line);padding:12px;background:#fff;border-radius:8px;min-width:0}
.mega-card:hover{border-color:#9cb3d9;box-shadow:0 5px 15px rgba(11,61,145,.08)}
.mega-card-logo{display:flex;align-items:center;gap:8px;min-height:27px}
.mega-card-logo img{width:25px;height:25px;object-fit:contain}
.mega-card strong,.mega-video-title,.mega-product-title{display:block;font-size:13px;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.mega-card p{margin:7px 0 0;color:var(--muted);font-size:12px;line-height:1.45}
.mega-card-meta{display:flex;flex-wrap:wrap;gap:5px 10px;margin-top:8px;color:#718096;font-size:11px}
.mega-video-cover,.mega-product-cover{width:100%;height:62px;object-fit:cover;border-radius:4px;margin-bottom:7px}
.mega-tool-icon{width:28px!important;height:28px!important}
.mega-layout{display:grid;grid-template-columns:145px 1fr;gap:20px}
.mega-categories{border-right:1px solid var(--line);padding-right:15px}
.mega-categories a{display:block;font-size:13px;padding:4px 0;color:#526174}
.header-btns{display:flex;align-items:center;gap:12px}
.header-member{font-size:14px;color:var(--blue);white-space:nowrap}
.header-open{background:var(--blue);color:#fff;border-radius:5px;padding:8px 16px;font-size:14px;white-space:nowrap}
.hamburger{display:none;border:0;background:transparent;padding:7px;cursor:pointer}
.hamburger span{display:block;width:23px;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(5,15,31,.48);opacity:0;visibility:hidden;z-index:80;transition:.2s}
.drawer-overlay.open{opacity:1;visibility:visible}
.mobile-drawer{position:fixed;top:0;right:0;bottom:0;width:min(360px,88vw);background:#fff;transform:translateX(100%);transition:.25s;z-index:90;overflow:auto}
.mobile-drawer.open{transform:translateX(0)}
.drawer-head{height:70px;display:flex;align-items:center;gap:17px;padding:0 20px;border-bottom:1px solid var(--line);color:var(--blue);font-weight:700}
.drawer-head>a{margin-left:auto;background:var(--blue);color:#fff;border-radius:4px;padding:5px 12px;font-size:13px}
.drawer-close{border:0;background:transparent;font-size:30px;color:#667085;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:none;text-align:left;font:inherit;color:var(--ink);cursor:pointer}
.drawer-toggle:after{content:"+";float:right;color:var(--blue);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:8px 0;color:#667085;font-size:14px}
.footer{margin-top:70px;background:#101b31;color:#c2ccdc}
.footer-main{display:grid;grid-template-columns:1.5fr 1fr 1fr 1.1fr;gap:40px;padding:48px 0 38px}
.footer .logo{color:#fff}.footer-brand p{max-width:340px;color:#aebbd0;font-size:14px;margin:17px 0}
.footer h3{font-size:15px;color:#fff;margin:4px 0 16px}
.footer-links,.footer-contact{display:grid;gap:9px;font-size:14px}
.footer-links a:hover,.footer-contact a:hover{color:#fff}
.footer-social a{color:#dbe7fb;font-size:13px}
.footer-bottom{border-top:1px solid rgba(255,255,255,.12);display:flex;justify-content:space-between;gap:20px;padding:17px 0;font-size:13px;color:#9eabc0}
.footer-bottom-links{display:flex;gap:18px}
.tool-detail-page{padding:34px 0 10px}
.breadcrumb{display:flex;gap:9px;align-items:center;color:#78869a;font-size:13px;margin-bottom:22px}
.breadcrumb a:hover{color:var(--blue)}
.tool-layout{display:grid;grid-template-columns:minmax(0,1fr) 300px;gap:28px;align-items:start}
.tool-main-card,.tool-side-card{background:#fff;border:1px solid var(--line);border-radius:12px;box-shadow:0 8px 24px rgba(23,32,51,.04)}
.tool-main-card{padding:32px}
.tool-heading{display:flex;align-items:center;gap:18px;padding-bottom:24px;border-bottom:1px solid var(--line)}
.tool-icon{width:72px;height:72px;object-fit:contain;border-radius:12px;background:#eef4fc;padding:12px}
.tool-heading h1{margin:0 0 6px;font-size:30px;line-height:1.3;color:#142b52}
.tool-heading p{margin:0;color:var(--muted);font-size:15px}
.tool-meta{display:flex;flex-wrap:wrap;gap:20px;margin:22px 0;padding:15px 18px;background:#f6f8fc;border-radius:8px;color:#65748a;font-size:13px}
.tool-meta strong{display:block;color:#263b5d;font-size:14px}
.tool-content{min-width:0;max-width:100%;overflow-x:auto;padding-top:4px;font-size:16px}
.tool-content h2,.tool-content h3{color:#163e78;margin:28px 0 12px}
.tool-content p{margin:0 0 16px}
.tool-content img,.tool-content table{max-width:100%;height:auto}
.tool-content ul,.tool-content ol{padding-left:24px}
.tool-actions{display:flex;gap:12px;margin-top:28px;padding-top:22px;border-top:1px solid var(--line)}
.primary-btn,.secondary-btn{display:inline-flex;align-items:center;justify-content:center;border-radius:5px;padding:10px 20px;font-size:14px}
.primary-btn{background:var(--blue);color:#fff}.secondary-btn{border:1px solid #b9c7dc;color:var(--blue)}
.tool-side-card{padding:22px;position:sticky;top:20px}
.tool-side-card h2{font-size:18px;margin:0 0 15px;color:#173b70}
.related-tool{display:grid;grid-template-columns:42px 1fr;gap:11px;padding:14px 0;border-top:1px solid var(--line)}
.related-tool img{width:42px;height:42px;object-fit:contain;background:#f0f5fc;border-radius:7px;padding:7px}
.related-tool strong{display:block;font-size:14px;margin-bottom:3px}
.related-tool p{margin:0;color:var(--muted);font-size:12px;line-height:1.45}
.side-more{display:block;margin-top:14px;color:var(--blue);font-size:13px;font-weight:700}
@media(max-width:1050px){
.main-nav{display:none}.hamburger{display:block}.header-inner{justify-content:space-between}.header-btns{margin-left:auto}
}
@media(max-width:760px){
.container{width:min(100% - 28px,1180px)}.topbar-inner{height:auto;min-height:38px;padding:7px 0;align-items:flex-start;gap:8px}.topbar-inner,.topbar-contact{flex-wrap:wrap}
.header-inner{height:68px;gap:10px}.header-member{display:none}.header-open{padding:7px 11px}
.tool-detail-page{padding-top:22px}.tool-layout{grid-template-columns:1fr;gap:18px}.tool-main-card{padding:20px}.tool-heading{align-items:flex-start}.tool-heading h1{font-size:24px}.tool-icon{width:58px;height:58px;flex:0 0 58px}
.tool-side-card{position:static}.footer-main{grid-template-columns:1fr 1fr;gap:28px;padding:36px 0}.footer-brand{grid-column:1/-1}
.footer-bottom{display:block}.footer-bottom-links{margin-top:8px}.mega-menu{display:none}
}
@media(max-width:460px){
.topbar-contact{font-size:12px}.footer-main{grid-template-columns:1fr}.footer-brand{grid-column:auto}.tool-actions{flex-direction:column}
}