:root{--bg:#F6FAFC;--surface:#fff;--soft:#EAF6FA;--soft2:#EDF4F8;--brand:#1787DB;--aqua:#25C8D1;--deep:#174B78;--title:#183A56;--text:#31485D;--muted:#687D8E;--line:#DCE9F0;--footer:#123653;--shadow:0 16px 46px rgba(23,75,120,.06)}
*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:24px}body{margin:0;background:var(--bg);color:var(--text);font:16px/1.8 Arial,'PingFang SC','Microsoft YaHei',sans-serif;overflow-x:hidden}a{color:var(--brand);text-decoration-thickness:1px;text-underline-offset:4px}a:hover{color:#075d9d}a:focus-visible,button:focus-visible,summary:focus-visible{outline:3px solid #19b9ca;outline-offset:3px}button{font:inherit;cursor:pointer}img{max-width:100%;height:auto}h1,h2,h3,p{margin-top:0}h1,h2,h3{color:var(--title);line-height:1.38}h1{font-size:clamp(27px,3.5vw,42px);letter-spacing:-.025em}h2{font-size:clamp(21px,2.2vw,27px)}h3{font-size:clamp(18px,1.7vw,21px)}p{margin-bottom:1.1em}.shell{width:min(1180px,calc(100% - 56px));margin-inline:auto}.section{margin-top:clamp(46px,5vw,64px);margin-bottom:clamp(46px,5vw,64px)}.section-heading{max-width:740px;margin-bottom:24px}.section-heading 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@media(max-width:1100px){.shortcut-inner{gap:8px}.shortcut-inner a{margin-left:5px}.shell{width:calc(100% - 44px)}}
@media(max-width:980px){.brandbar{height:62px;gap:12px}.menu-toggle{display:flex}.brand{margin-right:auto;justify-content:center}.brand img{max-height:30px;max-width:175px}.brand-note,.desktop-nav{display:none}.top-cta{min-height:40px;padding:7px 13px;font-size:12px}.shortcut-strip{display:none}.grid-7{grid-template-columns:repeat(3,minmax(0,1fr))}.hero{gap:22px}.reading-layout{grid-template-columns:minmax(0,1fr)}.info-aside{position:static;max-width:780px}}
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@media(max-width:640px){body{font-size:15px}.brand img{max-height:30px;max-width:140px}.brand-fallback{font-size:16px}.brand-fallback small{font-size:7px}.top-cta{font-size:12px;padding:6px 10px;gap:4px}.hero-copy p{font-size:15px}.section{margin-top:32px;margin-bottom:38px}.feature-panel,.story-block{padding:20px}.feature-panel h3{font-size:21px}.topic-card{padding:16px;gap:6px}.topic-card strong{font-size:16px}.topic-card>span:not(.eyebrow){font-size:13px}.media--hero{height:200px}.media--feature{height:180px}.media--card{height:145px}.media--banner{height:150px}.media--mobile{height:290px;max-width:250px}.media--panorama{height:auto;min-height:60px}.footer-grid{grid-template-columns:1fr 1fr}.bottom-nav{display:grid;position:fixed;bottom:0;left:0;right:0;z-index:18;grid-template-columns:repeat(4,1fr);min-height:58px;padding-bottom:env(safe-area-inset-bottom,0px);background:#fff;border-top:1px solid var(--line);box-shadow:0 -5px 25px rgba(23,75,120,.07)}.bottom-nav a{display:grid;place-items:center;color:var(--deep);text-decoration:none;font-size:13px;font-weight:700}.bottom-nav a[aria-current]{color:var(--brand);background:var(--soft)}body{padding-bottom:calc(58px + env(safe-area-inset-bottom,0px))}.back-to-top{bottom:calc(74px + env(safe-area-inset-bottom,0px))}.table-scroll{margin-inline:0}.steps{gap:9px}.steps li{padding:13px}.footer-bottom{font-size:11px}}
@media(max-width:360px){.brandbar{gap:4px}.brand img{max-width:108px}.top-cta{padding:5px 8px}.topic-card{padding:13px}.grid-7{gap:9px}}
@media(max-height:470px) and (max-width:640px){.bottom-nav{position:static}.back-to-top{bottom:20px}body{padding-bottom:0}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*,*:before,*:after{animation-duration:.01ms!important;transition-duration:.01ms!important}}

.nojs-nav{display:flex;flex-wrap:wrap;gap:8px;padding-block:12px}.nojs-nav a{display:inline-block;padding:5px 10px;border:1px solid var(--line);border-radius:5px;text-decoration:none;background:white;font-size:13px}