:root{--bg:#f5fbff;--white:#fff;--sub:#eaf7fc;--light:#dff5fb;--cyan:#25c8d1;--sky:#25b6e8;--blue:#1787db;--sea:#174b78;--heading:#173b60;--text:#2d4359;--muted:#687f93;--border:#dcebf3;--footer:#123653;--shadow:0 14px 35px rgba(23,75,120,.07)}
*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:92px}body{margin:0;background:var(--bg);color:var(--text);font:16px/1.8 Arial,"PingFang SC","Microsoft YaHei",sans-serif}body.menu-open{overflow:hidden}a{color:var(--blue);text-underline-offset:3px}a:hover{color:var(--sea)}button{font:inherit}img{max-width:100%}h1,h2,h3,p{margin-top:0}h1,h2,h3{color:var(--heading);line-height:1.4}h1{font-size:clamp(27px,3vw,40px);letter-spacing:-.7px}h2{font-size:clamp(20px,2.2vw,26px)}h3{font-size:19px}p{margin-bottom:17px}.wrap{width:min(1160px,calc(100% - 48px));margin-inline:auto}.skip-link{position:absolute;top:-100px;left:12px;z-index:200;padding:8px 15px;background:white}.skip-link:focus{top:6px}.site-header{background:white;position:sticky;top:0;z-index:50;box-shadow:0 1px 0 var(--border)}.header-inner{display:flex;align-items:center;gap:25px;min-height:72px}.brand{display:flex;align-items:center;gap:9px;color:var(--heading);font-weight:800;text-decoration:none;white-space:nowrap;flex:none}.brand img{display:block;width:auto;max-width:188px;height:36px;object-fit:contain}.brand-mark{width:39px;height:39px;display:grid;place-items:center;color:white;font-size:25px;background:linear-gradient(135deg,var(--cyan),var(--blue));border-radius:11px}.brand-copy{font-size:19px;line-height:1.05}.brand-copy small{display:block;color:var(--blue);font-size:9px;letter-spacing:1.7px;margin-top:5px}.desktop-nav{display:flex;align-items:center;justify-content:center;gap:15px;flex:1;white-space:nowrap}.desktop-nav a{color:var(--sea);text-decoration:none;font-size:14px;line-height:72px;font-weight:600;border-bottom:3px solid transparent}.desktop-nav a:hover,.desktop-nav 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.2s}.menu-overlay.is-open{visibility:visible;opacity:1;pointer-events:auto}.mobile-menu{position:fixed;z-index:80;top:0;bottom:0;left:0;width:min(86vw,350px);background:white;padding:20px 22px 36px;transform:translateX(-102%);visibility:hidden;overflow-y:auto;transition:transform .25s,visibility .25s;box-shadow:20px 0 50px rgba(0,0,0,.16)}.mobile-menu.is-open{transform:translateX(0);visibility:visible}.drawer-top{display:flex;justify-content:space-between;align-items:center;padding:0 0 15px;border-bottom:1px solid var(--border)}.drawer-heading{font-size:21px;font-weight:800;color:var(--heading)}.drawer-close{background:var(--sub);border:0;border-radius:10px;width:40px;height:40px;color:var(--sea);font-size:26px;cursor:pointer}.menu-group{display:grid;gap:3px;margin:20px 0}.menu-group>span{font-size:12px;font-weight:700;color:var(--muted);letter-spacing:1px;padding:0 12px 6px}.menu-group a{padding:9px 12px;color:var(--heading);text-decoration:none;font-weight:600;border-radius:8px}.menu-group a.is-active,.menu-group a:hover{color:var(--blue);background:var(--sub)}.page{padding:44px 0 72px}.eyebrow{display:inline-block;margin-bottom:15px;font-weight:800;font-size:12px;letter-spacing:2px;color:var(--blue);text-transform:uppercase}.hero{display:grid;grid-template-columns:1.04fr .96fr;align-items:center;gap:48px;padding:49px 53px;background:linear-gradient(120deg,#fff 35%,#eaf7fc 100%);border:1px solid var(--border);border-radius:24px;box-shadow:var(--shadow)}.hero h1{margin:0 0 20px}.hero p{font-size:17px}.hero-actions{display:flex;gap:12px;align-items:center;flex-wrap:wrap;margin-top:24px}.text-link{font-weight:700;text-decoration:none}.media{width:100%;min-height:190px;display:flex;align-items:center;justify-content:center;overflow:hidden;background:var(--sub);border-radius:15px;border:1px solid var(--border)}.media img{display:block;width:auto;height:auto;max-width:100%;max-height:100%;object-fit:contain;object-position:center}.hero-media{height:308px}.section-media{height:255px}.card-media{height:178px}.portrait-media{height:320px}.media-placeholder{display:flex;flex-direction:column;gap:9px;align-items:center;justify-content:center;width:100%;height:100%;min-height:inherit;padding:20px;text-align:center;color:var(--sea);font-size:13px;font-weight:600;background:linear-gradient(140deg,#eaf7fc,#dff5fb)}.placeholder-emblem{width:72px;height:72px;border:3px solid rgba(37,182,232,.28);border-radius:24px;transform:rotate(-12deg);background:linear-gradient(135deg,rgba(37,200,209,.28),rgba(23,135,219,.07))}.section{margin-top:50px}.section-heading{max-width:740px;margin-bottom:25px}.section-heading>p{color:var(--muted)}.cards{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:20px}.card{background:white;border:1px solid var(--border);border-radius:16px;padding:24px;box-shadow:0 5px 20px rgba(23,75,120,.035)}.card h3{margin-bottom:9px}.card p{font-size:15px}.card>a{font-weight:700;text-decoration:none}.card:focus-within,.card:hover{box-shadow:var(--shadow)}.card .tag,.tag{display:inline-block;color:var(--blue);font-size:12px;letter-spacing:1px;font-weight:800;margin-bottom:12px}.card .media{margin-bottom:17px}.article-grid{display:grid;grid-template-columns:1.38fr .8fr;gap:26px}.feature{padding:33px;background:white;border:1px solid var(--border);border-radius:18px}.feature h2{margin-bottom:20px}.feature ul,.article-body ul{padding-left:21px}.feature li,.article-body li{margin-bottom:8px}.sidebar-note{padding:28px;border-radius:18px;background:var(--sub);border:1px solid var(--border)}.sidebar-note h2{font-size:22px}.link-list{margin:0;padding:0;list-style:none}.link-list li{padding:10px 0;border-bottom:1px solid var(--border)}.link-list a{font-weight:700;text-decoration:none}.two-col{display:grid;grid-template-columns:1fr 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var(--border);border-radius:17px;padding:18px}.gallery-entry h3{margin-top:18px}.gallery-entry p{font-size:15px}.mini-index{display:flex;gap:10px;flex-wrap:wrap}.mini-index a{background:var(--sub);padding:7px 15px;border-radius:20px;font-size:14px;font-weight:700;text-decoration:none}.faq{border-bottom:1px solid var(--border);padding:15px 0}.faq h3{font-size:17px;margin-bottom:8px}.faq p{margin-bottom:0}.related{margin-top:55px;padding:25px 28px;background:var(--sub);border:1px solid var(--border);border-radius:18px}.related h2{font-size:21px;margin-bottom:16px}.related-links{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:10px}.related-links a{display:flex;justify-content:space-between;align-items:center;gap:8px;padding:12px 15px;background:white;color:var(--sea);border-radius:10px;font-size:14px;font-weight:700;text-decoration:none}.related-links a:hover{color:var(--blue)}.site-footer{background:var(--footer);color:#eaf7ff;padding:46px 0 17px}.site-footer 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rgba(255,255,255,.2);font-size:12px;opacity:.75}.bottom-nav{display:none}.back-to-top{position:fixed;bottom:24px;right:22px;z-index:40;width:42px;height:42px;border-radius:50%;border:0;background:var(--blue);color:white;font-weight:700;cursor:pointer;opacity:0;pointer-events:none;transition:opacity .2s}.back-to-top.is-visible{opacity:1;pointer-events:auto}
@media(max-width:1100px){.desktop-nav{gap:10px}.header-inner{gap:15px}.brand-copy{font-size:17px}.desktop-nav a{font-size:13px}}
@media(max-width:980px){.site-header .desktop-nav{display:none}.menu-toggle{display:block}.header-inner{justify-content:space-between;min-height:60px}.brand{margin-inline:auto}.brand img{height:30px;max-width:155px}.header-cta{min-height:39px;min-width:80px;padding:0 13px}.page{padding:32px 0 64px}.hero{padding:32px;gap:25px}.footer-grid{gap:25px}}
@media(max-width:700px){.wrap{width:calc(100% - 32px)}body{font-size:15px}.page{padding-top:22px;padding-bottom:50px}.hero{grid-template-columns:1fr;padding:24px 19px;border-radius:18px}.hero .media{grid-row:1;height:205px}.hero h1{font-size:29px}.hero p{font-size:15px}.section{margin-top:32px}.cards,.article-grid,.two-col,.compare,.gallery-grid,.footer-grid{grid-template-columns:1fr}.cards{gap:13px}.card{padding:20px}.feature,.text-panel,.sidebar-note{padding:21px}.section-heading{margin-bottom:17px}.article-head .intro{font-size:16px}.article-head{margin-bottom:20px}.article-body>section{margin-top:30px}.related{margin-top:35px;padding:19px}.related-links{grid-template-columns:1fr}.site-footer{padding-top:35px;padding-bottom:84px}.footer-nav{grid-template-columns:repeat(2,1fr)}.footer-bottom{flex-direction:column}.bottom-nav{position:fixed;z-index:42;bottom:0;left:0;right:0;display:grid;grid-template-columns:repeat(4,1fr);min-height:58px;padding-bottom:env(safe-area-inset-bottom);background:white;border-top:1px solid var(--border)}.bottom-nav a{display:grid;place-items:center;color:var(--sea);text-decoration:none;font-size:13px;font-weight:700}.bottom-nav a[aria-current=page]{color:var(--blue)}.back-to-top{bottom:80px;right:15px}.hero-media{height:205px}.section-media{height:195px}.card-media{height:155px}.portrait-media{height:255px}.footer-grid{gap:28px}.table-scroll{margin-inline:-4px}.info-table{font-size:14px}.info-table th,.info-table td{padding:10px 12px}}
@media(max-width:360px){.brand-copy{font-size:15px}.brand-copy small{font-size:8px;letter-spacing:1px}.brand-mark{height:33px;width:33px}.header-inner{gap:4px}.menu-toggle{width:38px}.header-cta{font-size:12px;padding:0 10px;min-width:72px}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*,*:before,*:after{transition:none!important;animation:none!important}}