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*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:30px}body{margin:0;background:var(--page);color:var(--body);font:16px/1.8 Arial,"PingFang SC","Microsoft YaHei",sans-serif;overflow-wrap:break-word}a{color:var(--deep);text-underline-offset:4px;text-decoration-thickness:1px}a:hover{color:var(--blue)}a:focus-visible,button:focus-visible,summary:focus-visible{outline:3px solid var(--cyan);outline-offset:3px}img{max-width:100%;height:auto}button{font:inherit;cursor:pointer}.container{width:min(100% - 56px,1180px);margin-inline:auto}.skip{position:absolute;left:12px;top:-100px;z-index:101;background:white;padding:8px 16px}.skip:focus{top:8px}.site-header{background:#fff;border-bottom:1px solid var(--line)}.toolbar{min-height:72px;display:flex;align-items:center;gap:24px}.brand{display:inline-flex;align-items:center;min-width:0;max-width:290px;text-decoration:none}.brand 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img{display:block;width:auto;height:auto;max-width:100%;max-height:100%;object-fit:contain;object-position:center}.media-placeholder{display:block;align-self:stretch;width:100%;background:linear-gradient(135deg,#EAF6FA,#EDF4F8)}.media--hero{height:clamp(250px,26vw,330px)}.media--feature{height:250px}.media--card{height:170px}.media--banner{height:220px}.media--mobile{height:350px;max-width:320px}.media--portrait{max-width:350px;margin-inline:auto}.media--wide img{width:100%;height:auto}.quick-strip{display:flex;flex-wrap:wrap;gap:8px 18px;align-items:center;border-bottom:1px solid var(--line);padding:17px 0;font-size:14px}.quick-strip strong{color:var(--ink)}.quick-strip a{white-space:nowrap}.topic-grid{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:14px}.topic-card{border:1px solid var(--line);background:#fff;border-radius:12px;padding:21px;text-decoration:none;display:block;min-width:0;transition:border-color .2s,transform .2s}.topic-card:hover{border-color:var(--cyan);transform:translateY(-2px)}.topic-card strong{font-size:18px;display:block;color:var(--ink);margin-bottom:6px}.topic-card p{font-size:14px;color:var(--muted);margin:0;line-height:1.65}.topic-card:last-child{grid-column:span 2}.editorial-grid{display:grid;grid-template-columns:2fr 1fr;gap:18px;align-items:stretch}.editorial-main{background:var(--sky);padding:32px;border-radius:16px}.editorial-side{display:grid;gap:18px}.editorial-side article{padding:22px;border-radius:14px;border:1px solid var(--line);background:#fff}.editorial-grid h3{margin-top:0}.split{display:grid;grid-template-columns:1fr 1fr;gap:30px;align-items:center}.split>*{min-width:0}.split--reverse .media{order:-1}.triple{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:16px}.small-feature{padding:23px;background:#fff;border-radius:14px;border:1px solid var(--line)}.small-feature h3{margin:0 0 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@media(max-width:980px){.container{width:min(100% - 44px,1180px)}.toolbar{height:64px;min-height:64px;justify-content:space-between;gap:12px}.brand{margin:auto}.brand img{max-height:30px}.brand-tagline,.desktop-nav{display:none}.entry-btn{font-size:13px;padding:8px 13px;min-height:40px}.menu-toggle{width:40px;height:40px;border:1px solid var(--line);border-radius:8px;display:flex;flex-direction:column;justify-content:center;align-items:center;gap:5px;background:#fff;flex-shrink:0}.menu-toggle span{width:19px;height:2px;background:var(--ink);display:block}.menu-close{display:block;font-size:28px;line-height:1;border:0;background:transparent;color:var(--ink);width:40px;height:40px}.menu-backdrop{display:block;position:fixed;inset:0;background:rgba(6,26,43,.52);z-index:90;visibility:hidden;opacity:0;pointer-events:none;transition:opacity .2s,visibility .2s}.mobile-drawer{display:block;position:fixed;z-index:91;top:0;left:0;bottom:0;width:min(86vw,344px);overflow-y:auto;background:#fff;box-shadow:var(--shadow);visibility:hidden;transform:translateX(-104%);transition:transform .22s,visibility .22s}.menu-open{overflow:hidden}.menu-open .menu-backdrop{visibility:visible;pointer-events:auto;opacity:1}.menu-open .mobile-drawer{visibility:visible;transform:translateX(0)}.drawer-head{display:flex;align-items:center;justify-content:space-between;border-bottom:1px solid var(--line);padding:14px 18px}.drawer-head strong{color:var(--ink);font-size:19px}.drawer-group{padding:15px 20px;border-bottom:1px solid var(--line)}.drawer-group h2{font-size:13px;color:var(--muted);margin:0 0 6px}.drawer-group a{display:block;padding:8px 9px;text-decoration:none;border-radius:7px}.drawer-group a[aria-current="page"]{background:var(--sky);font-weight:700}.topic-grid{grid-template-columns:repeat(3,minmax(0,1fr))}.topic-card:last-child{grid-column:span 1}.prose-columns{grid-template-columns:minmax(0,1fr) 220px;gap:20px}}
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@media(max-width:640px){body{font-size:15px;line-height:1.78}.container{width:calc(100% - 32px)}.toolbar{height:62px;min-height:62px}.entry-btn{padding:7px 10px;font-size:12px}.entry-btn span{display:none}.brand img{max-height:28px}.brand-text{font-size:16px}.brand-text small{font-size:8px}.page-heading h1,.hero h1{font-size:28px}.section>h2,.article h2{font-size:22px}.section h3,.article h3{font-size:18px}.lead{font-size:16px}.hero{margin-top:18px;padding:20px}.media--hero{height:200px}.media--feature{height:180px}.media--card{height:145px}.media--banner{height:150px}.media--mobile{height:290px;max-width:250px}.topic-grid,.triple,.matrix,.gallery{grid-template-columns:1fr}.topic-card:last-child{grid-column:auto}.topic-card{padding:17px}.surface,.soft-panel{padding:18px}.editorial-main{padding:22px}.steps{gap:9px}.feature-band{padding:18px}.quick-strip{gap:7px 11px}.related{margin-top:40px}.section{margin-top:34px}.page{padding-bottom:80px}.footer-bottom{flex-direction:column;gap:2px}.site-footer{padding-bottom:95px}.mobile-bottom{display:grid;grid-template-columns:repeat(4,1fr);position:fixed;bottom:0;left:0;right:0;z-index:20;background:#fff;border-top:1px solid var(--line);padding-bottom:env(safe-area-inset-bottom,0px);box-shadow:0 -3px 16px rgba(0,0,0,.06)}.mobile-bottom a{min-height:54px;display:flex;align-items:center;justify-content:center;text-decoration:none;font-size:13px;color:var(--body)}.mobile-bottom a[aria-current="page"]{color:var(--blue);font-weight:800;border-top:2px solid var(--blue)}.back-top{bottom:74px;right:12px}.footer-name span{display:block;margin:1px 0 0}}
@media(max-height:480px) and (max-width:640px){.mobile-bottom{position:static}.back-top{bottom:14px}.site-footer{padding-bottom:20px}}
@media(prefers-reduced-motion:reduce){*,*:before,*:after{scroll-behavior:auto!important;transition:none!important;animation:none!important}}

.noscript-nav{display:flex;flex-wrap:wrap;gap:7px 15px;padding:12px 0;border-bottom:1px solid var(--line)}.noscript-nav a{font-size:14px;padding:3px 0}