:root{--bg:#F4F7FA;--white:#fff;--soft:#EAF1F6;--mint:#E9F8F8;--navy:#102E46;--deep:#163C57;--teal:#13B8C5;--blue:#237BD3;--heading:#18364B;--text:#344C60;--muted:#64798A;--line:#DCE6ED;--footer:#0B2539;--space:clamp(30px,4.5vw,64px)}*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:20px}body{margin:0;background:var(--bg);color:var(--text);font:16px/1.8 Arial,'PingFang SC','Microsoft YaHei',sans-serif;overflow-wrap:anywhere}body.drawer-open{overflow:hidden}a{color:#176DAE;text-decoration-thickness:1px;text-underline-offset:4px}a:hover{color:#0D527F}button{font:inherit;cursor:pointer}a:focus-visible,button:focus-visible,summary:focus-visible{outline:3px solid 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@media(max-width:1100px){.brand-note{font-size:12px}.container{width:calc(100% - 44px)}}
@media(max-width:920px){.container{width:calc(100% - 44px)}.brand-inner{min-height:62px;display:grid;grid-template-columns:40px minmax(0,1fr) auto;gap:9px}.menu-toggle{display:flex;flex-direction:column;align-items:center;justify-content:center;gap:5px;width:40px;height:40px;background:transparent;border:1px solid #466477;border-radius:8px;color:#fff}.menu-toggle span{display:block;width:20px;height:2px;background:#fff}.site-logo{justify-self:center;max-width:100%}.site-logo img{max-height:30px;max-width:min(200px,100%)}.logo-placeholder{font-size:16px}.logo-placeholder small{font-size:8px}.brand-note,.desktop-nav{display:none}.entry-button{margin:0;min-height:40px;padding:6px 12px;font-size:13px}.drawer-overlay{display:block;position:fixed;inset:0;background:rgba(8,29,44,.55);opacity:0;visibility:hidden;pointer-events:none;transition:opacity .2s,visibility .2s;z-index:50}.mobile-drawer{display:flex;position:fixed;inset:0 auto 0 0;max-width:100%;width:min(86vw,340px);transform:translateX(-101%);visibility:hidden;pointer-events:none;transition:transform .22s,visibility .22s;background:#fff;z-index:51;flex-direction:column;padding:16px 20px;overflow-y:auto;box-shadow:6px 0 24px #102E4620}.drawer-open .drawer-overlay{opacity:1;visibility:visible;pointer-events:auto}.drawer-open .mobile-drawer{transform:translateX(0);visibility:visible;pointer-events:auto}.drawer-head{display:flex;align-items:center;justify-content:space-between;color:var(--heading)}.drawer-close{height:40px;width:40px;border:1px solid var(--line);border-radius:8px;background:#fff;font-size:26px;line-height:1}.drawer-group{font-size:12px;color:var(--muted);font-weight:800;letter-spacing:.1em;margin:21px 0 7px;padding-bottom:5px;border-bottom:1px solid var(--line)}.mobile-drawer a{padding:10px;border-radius:8px;text-decoration:none;font-weight:700}.mobile-drawer a[aria-current]{background:var(--mint);border-left:3px solid var(--teal)}.nojs-nav{display:none}.mobile-quick{display:flex;justify-content:space-around;flex-wrap:wrap;gap:10px;padding:20px 0;font-size:13px}.mobile-quick a{font-weight:700}body:not(.drawer-open) .mobile-drawer{pointer-events:none}}
@media(max-width:760px){.hero-grid,.split-panel,.split-panel--wide,.editorial-grid,.content-columns,.service-grid,.footer-layout{grid-template-columns:minmax(0,1fr)}.hero-grid{gap:24px}.section-heading{align-items:flex-start}.three-grid,.comparison-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.rule-teasers{grid-template-columns:1fr}.rule-teasers article:nth-child(n){margin-top:0}.steps{grid-template-columns:repeat(2,minmax(0,1fr))}.fact-aside{position:static}.service-aside{position:static;order:2}.service-main{order:1}.related-links{grid-template-columns:1fr}.gallery-grid{gap:17px}.footer-layout{gap:22px}}
@media(max-width:640px){:root{--space:36px}.container{width:calc(100% - 32px)}body{font-size:15px;line-height:1.76}h1{font-size:clamp(25px,6.7vw,29px)}h2{font-size:clamp(20px,5.5vw,23px)}h3{font-size:18px}.home-hero{padding-block:34px}.home-hero h1{font-size:clamp(27px,7vw,32px)}.page-intro{padding-block:30px 18px}.lead{font-size:15px}.topic-directory,.gallery-grid,.three-grid,.comparison-grid{grid-template-columns:1fr}.gallery-grid article:nth-child(n){margin-top:0}.topic-item{padding:15px 0}.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}.media-frame--hero.media-placeholder{min-height:145px}.section-heading{display:block}.section-heading h2{margin-bottom:8px}.steps{gap:14px}.numbered-sections>article{padding-left:48px}.feature-story,.mini-story{padding:20px}.footer-bottom{display:block}.footer-bottom span{display:block;margin-bottom:6px}.action-row{align-items:stretch}.action-row a{flex:1}.footer-links{gap:9px}.anchor-nav a{font-size:13px}}
@media(max-width:370px){.entry-button{padding:6px 8px;font-size:12px}.site-logo img{max-width:142px}.logo-placeholder{font-size:14px}.brand-inner{gap:5px}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*,*:before,*:after{transition-duration:.01ms!important;animation-duration:.01ms!important}}
@media print{.menu-toggle,.entry-button,.mobile-quick,.back-top,.desktop-nav,.drawer-overlay,.mobile-drawer{display:none!important}.site-footer{background:#fff;color:#333}.container{width:100%}a{color:inherit}}