:root{--bg:#F4F7FA;--paper:#fff;--soft:#EAF1F6;--mint:#E9F8F8;--nav:#102E46;--deep:#163C57;--cyan:#13B8C5;--blue:#237BD3;--title:#18364B;--text:#344C60;--muted:#64798A;--line:#DCE6ED;--footer:#0B2539;--wrap:1200px;font-family:Arial,"PingFang SC","Microsoft YaHei",sans-serif;color:var(--text);background:var(--bg)}
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0}.two-col{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:28px}.three-col{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:20px}.split{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1fr);gap:38px;align-items:center}.split>*{min-width:0}.split-wide{grid-template-columns:1.15fr .85fr}.split-reverse{grid-template-columns:.83fr 1.17fr}.media-frame{display:flex;justify-content:center;align-items:center;min-width:0;width:100%;margin:0;padding:9px;background:var(--soft);border-radius:13px}.media-frame img{display:block;width:auto;height:auto;max-width:100%;max-height:var(--media-limit,220px);object-fit:contain;object-position:center}.media-frame--hero{--media-limit:310px}.media-frame--feature{--media-limit:250px}.media-frame--card{--media-limit:185px}.media-frame--mobile{--media-limit:350px;max-width:320px;margin-inline:auto}.media-frame--banner{--media-limit:210px}.media-placeholder{min-height:115px;border:1px dashed #B8CDD8;color:#657E8F;font-size:.82rem;text-align:center}.media-frame--hero.media-placeholder{min-height:190px}.media-frame--mobile.media-placeholder{min-height:220px}.cover{padding:55px 0 32px}.cover .split{grid-template-columns:1.08fr 1fr}.cover-intro p{max-width:605px}.topic-directory{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:0 32px}.topic-item{border-bottom:1px solid var(--line);padding:21px 0}.topic-item a{font-size:1.16rem;font-weight:750;color:var(--title)}.topic-item a:hover{color:var(--blue)}.topic-item p{margin:6px 0 0;font-size:.93rem}.feature-layout{display:grid;grid-template-columns:2fr 1fr;gap:24px}.feature-side{display:flex;flex-direction:column;gap:18px}.feature-side article{border-bottom:1px solid var(--line);padding:7px 0 12px}.feature-side article:last-child{border:0}.feature-main{padding:31px;background:#E9F8F8;border-radius:12px}.steps{counter-reset:step;display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:13px}.steps 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0}.data-table{border-collapse:collapse;background:white;width:100%;min-width:570px;font-size:.93rem;line-height:1.65}.data-table caption{text-align:left;color:var(--title);padding:14px 16px;font-weight:700}.data-table th,.data-table td{text-align:left;padding:14px 16px;border-bottom:1px solid var(--line);vertical-align:top}.data-table th{background:#EAF1F6;color:var(--title)}.data-table tr:last-child td{border-bottom:none}.gallery-grid{display:grid;grid-template-columns:1fr 1fr;gap:30px;align-items:start}.gallery-grid>*{min-width:0}.gallery-grid article:nth-child(2){margin-top:55px}.gallery-grid article:nth-child(3){grid-column:1 / -1;display:grid;grid-template-columns:1.1fr .9fr;gap:26px;align-items:center}.gallery-grid article:nth-child(3)>*{min-width:0}.faq-list details{border-bottom:1px solid var(--line);background:#fff;padding:0 18px}.faq-list details:first-child{border-top:1px solid var(--line)}.faq-list summary{cursor:pointer;padding:14px 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section{margin-bottom:46px}.site-footer{background:var(--footer);color:#DCECF5;margin-top:65px;padding:45px 0 0;font-size:.9rem}.footer-grid{display:grid;grid-template-columns:1.3fr .7fr;gap:80px}.footer-grid p{max-width:660px}.footer-logo{font-size:1.3rem;font-weight:800;color:white}.footer-logo span{font-size:.73rem;font-weight:500;letter-spacing:.08em;color:#9FDCE3}.site-footer h2{color:white;font-size:1.05rem}.footer-links{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:9px}.footer-links a,.footer-bottom a{color:#DCECF5}.footer-bottom{display:flex;align-items:center;justify-content:space-between;border-top:1px solid #355064;padding:16px 0;margin-top:25px;color:#BDD2DC}.mobile-quick{display:none}.back-top{position:fixed;right:22px;bottom:22px;border:0;border-radius:50%;background:var(--nav);color:#fff;width:44px;height:44px;cursor:pointer;font-size:1.4rem;box-shadow:0 3px 14px #0002}.back-top[hidden]{display:none}
@media(max-width:1024px){.shell{width:min(calc(100% - 44px),var(--wrap))}.brand-desc{display:none}.content-layout{gap:26px;grid-template-columns:minmax(0,1fr) 215px}.section{margin-block:48px}}
@media(max-width:920px){.brand-inner{height:62px;justify-content:space-between;gap:9px}.brand{position:absolute;left:50%;transform:translateX(-50%);max-width:calc(100% - 190px);justify-content:center}.brand img{max-height:30px;max-width:100%}.brand-fallback{font-size:1rem}.entry-link{margin-left:auto;padding:9px 12px;font-size:.83rem;min-height:39px}.menu-toggle{width:40px;height:40px;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:5px;padding:0;border:1px solid var(--line);border-radius:8px;background:#fff;cursor:pointer;flex-shrink:0}.menu-toggle span{width:18px;height:2px;background:var(--title)}.desktop-nav{display:none}.drawer-overlay{display:block;position:fixed;inset:0;background:#0A2539a8;opacity:0;visibility:hidden;pointer-events:none;z-index:100;transition:opacity .2s,visibility .2s}.drawer-overlay.is-open{opacity:1;visibility:visible;pointer-events:auto}.mobile-drawer{display:block;position:fixed;inset:0 auto 0 0;width:min(86vw,340px);background:#fff;z-index:101;transform:translateX(-101%);visibility:hidden;transition:transform .25s,visibility .25s;overflow-y:auto;padding:20px 22px;box-shadow:8px 0 30px #0002}.mobile-drawer.is-open{transform:translateX(0);visibility:visible}.drawer-head{display:flex;align-items:center;justify-content:space-between;padding-bottom:16px;border-bottom:1px solid var(--line)}.drawer-close{font-size:2rem;background:none;border:0;cursor:pointer;line-height:1}.mobile-drawer nav h2{font-size:.85rem;color:var(--muted);margin:23px 0 6px}.mobile-drawer nav a{display:block;padding:10px 7px;color:var(--title);font-weight:600;border-bottom:1px solid var(--line)}body.menu-open{overflow:hidden}.nojs-nav{display:none}.mobile-quick{display:flex;gap:15px;justify-content:center;flex-wrap:wrap;padding-block:25px;border-top:1px solid var(--line)}.mobile-quick a{font-size:.88rem}.site-footer{margin-top:0}.cover{padding-top:35px}}
@media(max-width:760px){.content-layout,.service-layout{grid-template-columns:1fr}.aside-notes{order:2}.service-side{position:static;order:2}.service-body{order:1}.split,.split-wide,.split-reverse,.cover .split{grid-template-columns:1fr}.cover .media-frame{max-width:680px;margin-inline:auto}.two-col,.feature-layout{grid-template-columns:1fr}.feature-side{display:grid;grid-template-columns:repeat(2,minmax(0,1fr))}.steps{grid-template-columns:repeat(2,minmax(0,1fr))}.gallery-grid article:nth-child(2){margin-top:0}.footer-grid{gap:28px}}
@media(max-width:640px){body{font-size:15.5px}.shell{width:calc(100% - 32px)}h1{font-size:clamp(1.68rem,7vw,2rem)}h2{font-size:clamp(1.3rem,5.3vw,1.45rem)}h3{font-size:1.09rem}.section{margin-block:36px}.cover{padding:30px 0 10px}.section-header{display:block}.section-header p{margin-top:8px}.topic-directory,.three-col,.info-strip,.gallery-grid,.feature-side,.related-list{grid-template-columns:1fr}.gallery-grid article:nth-child(3){grid-column:auto;display:block}.panel,.soft-panel,.feature-main,.dark-band{padding:19px}.steps{gap:10px}.steps article{padding:15px}.media-frame--hero{--media-limit:205px}.media-frame--feature{--media-limit:185px}.media-frame--card{--media-limit:145px}.media-frame--banner{--media-limit:135px}.media-frame--mobile{--media-limit:285px;max-width:250px}.footer-grid{grid-template-columns:1fr;gap:20px}.footer-bottom{display:block}.footer-bottom a{display:block;margin-top:5px}.reading-index a{display:block;margin:5px 0}.breadcrumbs{padding-top:17px;margin-bottom:18px}.site-footer{padding-top:31px}.brand{max-width:calc(100% - 168px)}}
@media(max-width:380px){.brand{max-width:calc(100% - 160px)}.brand img{max-height:27px}.entry-link{font-size:.75rem;padding:8px}.steps{grid-template-columns:1fr}.brand-fallback small{display:none}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*,*:before,*:after{animation-duration:.01ms!important;transition-duration:.01ms!important}}
@media print{.site-header,.site-footer,.back-top,.mobile-quick{display:none!important}body{background:#fff;color:#222}.shell{width:100%}}

@media(max-width:920px){.nojs-nav{display:flex;flex-wrap:wrap;gap:10px;padding-block:10px}.nojs-nav a{font-size:.78rem;padding:4px 7px;background:#EAF1F6;border-radius:4px}.js-enabled .nojs-nav{display:none}}