:root{--bg:#F4F7FA;--paper:#fff;--tint:#EAF1F6;--mint:#E9F8F8;--nav:#102E46;--nav2:#163C57;--aqua:#13B8C5;--blue:#237BD3;--ink:#18364B;--text:#344C60;--muted:#64798A;--line:#DCE6ED;--footer:#0B2539;--width:1200px}*{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:break-word}body.menu-open{overflow:hidden}h1,h2,h3{color:var(--ink);line-height:1.38;letter-spacing:-.025em}h1{font-size:clamp(27px,3.4vw,42px);margin:12px 0 20px}h2{font-size:clamp(21px,2.2vw,28px);margin:0 0 18px}h3{font-size:19px;margin:0 0 12px}p{margin:0 0 17px}a{color:#1369ad;text-underline-offset:4px}a:hover{color:#0c548d}button{font:inherit;cursor:pointer}button,a{touch-action:manipulation}:focus-visible{outline:3px solid var(--aqua);outline-offset:3px}img{max-width:100%}.container{width:min(var(--width),calc(100% - 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20px;border-radius:9px;background:var(--nav);color:#fff}.button:hover{color:#fff;background:var(--nav2)}.button.secondary{background:var(--mint);color:#0c586b}.hero .media-frame{margin:0}.media-frame{display:flex;align-items:center;justify-content:center;min-width:0;margin:0;background:var(--tint);border:1px solid var(--line);border-radius:14px;padding:9px;overflow:hidden}.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--banner{--media-limit:210px}.media-frame--mobile{--media-limit:350px;max-width:320px;margin-inline:auto}.media-placeholder{display:grid;place-items:center;min-height:125px;width:100%;color:#687f91;background:repeating-linear-gradient(135deg,#eaf1f6 0 12px,#f3f7f9 12px 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@media(max-width:1024px){.container{width:calc(100% - 44px)}.nav-inner{gap:4px}.nav-inner a{font-size:13px}.section{margin-block:48px}}
@media(max-width:920px){.brand-inner{min-height:62px;display:grid;grid-template-columns:40px minmax(0,1fr) auto;gap:10px}.menu-toggle{display:flex;width:40px;height:40px;flex-direction:column;align-items:center;justify-content:center;gap:5px;border:1px solid var(--line);border-radius:8px;background:white}.menu-toggle span{height:2px;background:var(--nav);width:20px}.brand{justify-self:center;max-width:100%}.brand img{max-height:29px;max-width:min(200px,100%)}.brand-fallback{font-size:16px}.brand-fallback small{font-size:8px}.brand-note,.desktop-nav{display:none}.entry-link{margin-left:0;padding:8px 10px;font-size:12px;white-space:nowrap}.mobile-overlay{display:block;position:fixed;inset:0;background:#071927a8;opacity:0;visibility:hidden;pointer-events:none;transition:opacity .2s,visibility .2s;z-index:40}.mobile-menu{display:block;position:fixed;z-index:41;inset:0 auto 0 0;width:min(86vw,340px);max-width:100%;background:white;box-shadow:15px 0 35px #07192720;padding:18px 20px;overflow-y:auto;transform:translateX(-104%);visibility:hidden;pointer-events:none;transition:transform .22s,visibility .22s}.menu-open .mobile-overlay{opacity:1;visibility:visible;pointer-events:auto}.menu-open .mobile-menu{transform:translateX(0);visibility:visible;pointer-events:auto}.mobile-menu-head{display:flex;align-items:center;justify-content:space-between;border-bottom:1px solid var(--line);padding-bottom:14px}.menu-close{background:var(--tint);border:0;border-radius:8px;font-size:24px;width:40px;height:40px}.mobile-menu .menu-group-title{font-size:12px;color:#64798a;font-weight:800;letter-spacing:.13em;margin:22px 0 6px}.mobile-menu>a{display:block;padding:9px 4px;color:var(--ink);text-decoration:none;border-radius:7px;font-weight:600}.mobile-menu>a[aria-current]{background:var(--mint);border-left:3px solid var(--aqua);padding-left:12px}.nojs-nav{display:flex;overflow-x:auto;gap:16px;background:var(--nav);padding:10px 22px}.nojs-nav a{white-space:nowrap;color:white}.mobile-shortcuts{display:flex;flex-wrap:wrap;justify-content:center;gap:9px 22px;margin:35px 16px 0;font-size:13px}.hero-grid{gap:20px}}
@media(max-width:760px){.article-shell,.media-text,.media-text.reverse,.hero-grid,.service-layout{grid-template-columns:1fr}.hero-grid .media-frame{order:2}.hero-grid>div{order:1}.article-shell aside{order:2}.focus-layout,.split-list,.footer-layout{grid-template-columns:1fr}.story-stack{grid-template-columns:1fr 1fr}.rule-trio{grid-template-columns:1fr}.rule-trio article:nth-child(n){margin-top:0}.flow-steps{grid-template-columns:repeat(2,1fr)}.editor-grid{grid-template-columns:1fr}.service-layout aside{order:2}.service-layout>div{order:1}.hero{padding:38px 0}.page-lead{padding:38px 0}.section{margin-block:42px}.text-panel{padding:21px}}
@media(max-width:640px){body{font-size:15px;line-height:1.78}.container{width:calc(100% - 32px)}h1{font-size:clamp(27px,7vw,32px)}h2{font-size:clamp(20px,5vw,23px)}h3{font-size:17px}.page-lead h1{font-size:clamp(25px,6.6vw,29px)}.lead-text{font-size:16px}.hero{padding:32px 0}.hero-actions{gap:10px}.button{padding:9px 13px;font-size:14px}.topic-directory{padding:35px 0}.index-columns,.gallery-grid,.story-stack{grid-template-columns:1fr}.gallery-piece:nth-child(even){margin-top:0}.index-entry{padding:16px 0}.section{margin-block:34px}.section-sm{margin-block:30px}.feature-story{padding:22px}.feature-story h3{font-size:21px}.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:160px}.media-frame--mobile .media-placeholder{min-height:190px}.page-lead{padding:28px 0}.flow-steps{grid-template-columns:1fr 1fr}.dark-band,.accent-band{padding:34px 0}.gallery-piece{padding:14px}.gallery-piece p{font-size:14px}.related{padding:20px}.site-footer{margin-top:40px}.footer-bottom{flex-direction:column}.footer-layout{gap:20px}.site-footer nav{grid-template-columns:repeat(2,minmax(0,1fr))}}
@media(max-width:380px){.entry-link{font-size:11px;padding:8px}.brand img{max-width:145px}.brand-inner{gap:7px}.flow-steps{grid-template-columns:1fr}}@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*,*:before,*:after{animation-duration:.01ms!important;transition-duration:.01ms!important}}