:root{--bg:#F4F7FA;--white:#fff;--soft:#EAF1F6;--mint:#E9F8F8;--navy:#102E46;--deep:#163C57;--teal:#13B8C5;--blue:#237BD3;--ink:#18364B;--text:#344C60;--muted:#64798A;--line:#DCE6ED;--footer:#0B2539}*{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:#176BAE;text-underline-offset:3px}a:hover{color:#0d566f}button{font:inherit;cursor:pointer}h1,h2,h3,h4{color:var(--ink);line-height:1.37;margin:0 0 .8em;font-weight:750}h1{font-size:clamp(32px,3.1vw,42px)}h2{font-size:clamp(24px,2.3vw,28px)}h3{font-size:20px}p{margin:0 0 1.15em}ul,ol{padding-left:1.4em}li{margin:.25em 0}section[id],article[id]{scroll-margin-top:32px}.container{width:min(1200px,calc(100% - 56px));margin-inline:auto}.section-space{margin-top:60px;margin-bottom:60px}.eyebrow{font-size:13px;font-weight:750;letter-spacing:.12em;color:#168A99;text-transform:uppercase}.lead{font-size:18px;color:#4D6576;max-width:800px}.pill{display:inline-flex;align-items:center;justify-content:center;text-decoration:none;background:var(--deep);color:#fff;padding:10px 21px;border-radius:8px;font-weight:700;min-height:44px}.pill:hover{background:#0F5972;color:#fff}.pill--light{background:#E9F8F8;color:#155D67}.pill--light:hover{background:#D3F1F2;color:#12434D}.button-line{display:flex;gap:12px;flex-wrap:wrap;margin-top:26px}.skip-link{position:absolute;left:10px;top:-100px;padding:10px 14px;background:#fff;z-index:200}.skip-link:focus{top:10px}:focus-visible{outline:3px solid #16b7c7;outline-offset:3px}.site-header{background:var(--navy);color:#fff}.brand-bar{background:var(--navy)}.brand-inner{display:flex;align-items:center;gap:22px;min-height:72px}.brand-logo{display:flex;align-items:center;text-decoration:none;color:#fff;min-width:0;flex-shrink:0}.brand-logo img{display:block;width:auto;height:auto;max-height:38px;max-width:200px;object-fit:contain}.logo-fallback{font-size:22px;line-height:1;font-weight:800;white-space:nowrap}.logo-fallback small{display:block;font-size:9px;letter-spacing:.17em;margin-top:6px;color:#9CE5EC}.brand-descriptor{margin:0;color:#BBD3E1;font-size:13px;letter-spacing:.03em}.brand-descriptor span{margin:0 8px;color:#62899C}.entry-link{margin-left:auto;background:var(--teal);color:#092E3A;text-decoration:none;white-space:nowrap;border-radius:8px;padding:8px 19px;font-weight:800;min-height:43px;display:inline-flex;align-items:center}.entry-link:hover{background:#6EE1E8;color:#07313D}.desktop-nav{background:#102E46;border-top:1px solid rgba(255,255,255,.11)}.nav-inner{display:grid;grid-template-columns:repeat(7,minmax(0,1fr));gap:6px;min-height:50px}.desktop-nav a{position:relative;display:flex;align-items:center;justify-content:center;text-decoration:none;white-space:nowrap;font-size:14px;font-weight:650;color:#D8E6EF;padding:8px 3px}.desktop-nav a:hover,.desktop-nav a.is-current{color:#fff}.desktop-nav a.is-current{font-weight:800}.desktop-nav a.is-current:after{content:"";position:absolute;bottom:0;left:28%;right:28%;height:3px;border-radius:3px;background:var(--teal)}.no-js-nav{display:none}.menu-toggle{display:none}.drawer-backdrop,.mobile-drawer{display:none}.site-footer{background:var(--footer);color:#DCECF5;padding:43px 0 0}.footer-grid{display:grid;grid-template-columns:1.4fr 1fr;gap:60px}.footer-grid p{font-size:14px;max-width:600px}.footer-brand{font-size:22px!important;font-weight:800}.footer-brand span{font-size:11px;letter-spacing:.12em;color:#8DD6DE;margin-left:10px}.footer-heading{font-weight:800;color:#fff}.footer-links{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:6px 18px}.site-footer a{color:#DCECF5;text-decoration:none;font-size:14px}.site-footer a:hover{color:#6FE1EA}.footer-bottom{border-top:1px solid #355066;padding:18px 0 22px;margin-top:32px;font-size:12px;color:#BDD1DF}.mobile-shortcuts{display:none}.back-top{position:fixed;right:21px;bottom:23px;border:0;border-radius:50%;width:44px;height:44px;background:#163C57;color:#fff;box-shadow:0 4px 20px #1234;z-index:30}.back-top[hidden]{display:none}.page-intro{padding:54px 0 32px}.page-intro .lead{max-width:850px}.page-hero-note{background:#E9F8F8;border-left:4px solid var(--teal);padding:15px 19px;margin-top:25px}.breadcrumbs{font-size:13px;color:var(--muted);margin-bottom:18px}.breadcrumbs a{color:#507489;text-decoration:none}.reading-layout{display:grid;grid-template-columns:minmax(0,1fr) 260px;gap:45px;align-items:start}.reading-column{min-width:0;max-width:800px}.reading-column h2{margin-top:38px}.reading-column h2:first-child{margin-top:0}.reading-column h3{margin-top:24px}.reading-column p{line-height:1.85}.aside-index,.info-panel{background:#fff;border:1px solid var(--line);border-radius:13px;padding:22px}.aside-index{position:sticky;top:24px}.aside-index a{display:block;padding:9px 0;border-bottom:1px solid var(--line);text-decoration:none}.aside-index a:last-child{border-bottom:0}.page-section{padding:0 0 42px;margin:0 0 42px;border-bottom:1px solid var(--line)}.page-section:last-child{border-bottom:0}.soft-panel{background:var(--soft);border-radius:14px;padding:27px}.mint-panel{background:var(--mint);border-radius:14px;padding:27px}.dark-panel{background:var(--deep);color:#DFEFF5;border-radius:14px;padding:30px}.dark-panel h2,.dark-panel h3{color:#fff}.dark-panel a{color:#80EFF2}.label-line{font-weight:800;color:#148898;margin-bottom:8px}.compact-list{padding-left:20px}.caption-note{font-size:13px;color:var(--muted)}.media-frame{display:flex;align-items:center;justify-content:center;margin:0;width:100%;min-width:0;min-height:78px;padding:9px;background:#EAF1F6;border-radius:14px;--media-limit:220px}.media-frame img{display:block;width:auto;height:auto;max-width:100%;max-height:var(--media-limit);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-missing{border:1px dashed #BFD2DF;color:#678595;font-size:13px;min-height:120px;text-align:center}.media-frame--hero.media-missing{min-height:210px}.media-frame--card.media-missing{min-height:110px}.media-frame--mobile.media-missing{min-height:200px}.media-missing span{padding:20px}.cover{display:grid;grid-template-columns:52fr 48fr;align-items:center;gap:35px;padding:64px 0 30px}.cover-copy h1{max-width:610px}.cover-copy p{max-width:570px}.cover-copy .eyebrow{margin-bottom:15px}.section-heading{display:flex;justify-content:space-between;align-items:end;gap:25px;margin-bottom:25px}.section-heading p{max-width:560px}.topic-index{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:0 40px;border-top:2px solid var(--ink)}.topic-item{border-bottom:1px solid var(--line);padding:21px 0}.topic-item h3{margin:0 0 7px;font-size:19px}.topic-item p{margin:0 0 8px;font-size:14px}.topic-item a{font-weight:700}.editorial-grid{display:grid;grid-template-columns:minmax(0,2fr) minmax(0,1fr);gap:24px}.editorial-feature{padding:31px;background:#fff;border-top:4px solid var(--teal)}.editorial-side{display:grid;gap:18px}.editorial-side article{background:var(--soft);padding:22px}.editorial-side h3{font-size:18px}.split{display:grid;grid-template-columns:1fr 1fr;gap:34px;align-items:center}.split--wide{grid-template-columns:1.15fr .85fr}.split--reverse{grid-template-columns:.85fr 1.15fr}.three-columns{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:18px}.knowledge-block{padding:24px;background:white;border:1px solid var(--line);border-radius:12px}.knowledge-block:nth-child(2){transform:translateY(14px)}.knowledge-block:nth-child(3){transform:translateY(28px)}.reading-steps{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:18px;counter-reset:step}.reading-steps>div{border-top:3px solid var(--teal);padding-top:14px}.reading-steps>div:before{counter-increment:step;content:'0' counter(step);display:block;font-size:22px;font-weight:800;color:#158b97}.reading-steps h3{font-size:18px}.related-reading{border-top:2px solid #1E5367;padding-top:22px}.related-list{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:12px}.related-list a{display:flex;justify-content:space-between;gap:12px;background:#fff;border:1px solid var(--line);padding:18px;text-decoration:none;font-weight:750;border-radius:9px}.related-list span{color:#13A7B5}.table-scroll{overflow-x:auto;max-width:100%;margin:20px 0 30px;border:1px solid var(--line);border-radius:12px;background:#fff}table{border-collapse:collapse;width:100%;font-size:15px;min-width:560px}caption{text-align:left;padding:14px 16px;font-weight:750;color:var(--ink)}th,td{text-align:left;vertical-align:top;border-bottom:1px solid var(--line);padding:12px 15px}th{color:#14354C;background:#EAF1F6}tr:last-child td{border-bottom:0}.sequence{counter-reset:sequence;list-style:none;padding:0;display:grid;gap:16px}.sequence li{position:relative;padding:18px 20px 18px 65px;border-left:3px solid var(--teal);background:#fff;counter-increment:sequence}.sequence li:before{content:counter(sequence);position:absolute;left:20px;top:16px;font-size:23px;font-weight:800;color:#108c9a}.sequence strong{color:var(--ink)}.compare-matrix{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:14px}.compare-matrix article{background:#fff;border-top:4px solid var(--teal);padding:20px}.compare-matrix h3{font-size:20px}.exhibition{display:grid;grid-template-columns:1fr 1fr;gap:36px;align-items:start}.exhibition article:nth-child(even){margin-top:55px}.exhibition article{min-width:0}.exhibition .media-frame{margin-bottom:16px}.toc-pills{display:flex;flex-wrap:wrap;gap:10px;margin:20px 0}.toc-pills a{border:1px solid #B9D6DD;padding:8px 15px;border-radius:99px;background:#fff;text-decoration:none;font-weight:700}.fact-chip{display:inline-block;background:#DDF4F4;color:#126A75;padding:2px 10px;border-radius:5px;font-size:13px;font-weight:700}.faq-list details{background:#fff;border:1px solid var(--line);border-radius:9px;margin-bottom:10px;padding:0 17px}.faq-list summary{cursor:pointer;font-weight:760;padding:14px 0;color:var(--ink)}.faq-list details p{padding:0 0 15px;margin:0}.service-grid{display:grid;grid-template-columns:240px minmax(0,1fr);gap:36px;align-items:start}.service-nav{padding:20px;background:#fff;border:1px solid var(--line);border-radius:12px}.service-nav a{display:block;padding:8px 0}.service-content{min-width:0}.service-content section{margin-bottom:40px}.quote-strip{border-left:5px solid var(--teal);background:var(--mint);padding:20px 25px;font-size:18px;color:#24576A}.footnote{font-size:13px;color:#627C8D}.editorial-statement{border-top:1px solid var(--line);padding:28px 0;margin-top:35px;font-size:14px;color:var(--muted)}
@media(max-width:1100px){.container{width:calc(100% - 44px)}.brand-descriptor{font-size:12px}.reading-layout{gap:28px;grid-template-columns:minmax(0,1fr) 225px}}
@media(max-width:920px){.brand-inner{min-height:63px;position:relative;justify-content:space-between;gap:12px}.brand-logo{position:absolute;left:50%;transform:translateX(-50%);max-width:42%}.brand-logo img{max-height:30px;max-width:100%}.logo-fallback{font-size:15px}.logo-fallback small{font-size:7px}.brand-descriptor,.desktop-nav{display:none}.menu-toggle{display:flex;flex-direction:column;align-items:center;justify-content:center;gap:5px;width:40px;height:40px;flex-shrink:0;background:transparent;border:1px solid #7693A7;border-radius:8px;padding:0}.menu-toggle span{display:block;width:19px;height:2px;background:#fff}.entry-link{margin-left:auto;min-height:40px;padding:5px 11px;font-size:13px}.drawer-backdrop{display:block;position:fixed;inset:0;background:rgba(6,26,39,.54);z-index:80;opacity:0;visibility:hidden;pointer-events:none;transition:opacity .2s,visibility .2s}.drawer-backdrop.is-open{opacity:1;visibility:visible;pointer-events:auto}.mobile-drawer{display:flex;flex-direction:column;position:fixed;top:0;bottom:0;left:0;width:min(86vw,340px);max-width:100%;background:#fff;z-index:81;transform:translateX(-102%);visibility:hidden;transition:transform .22s,visibility .22s;overflow-y:auto;padding:21px 22px;box-shadow:8px 0 26px #0002}.mobile-drawer.is-open{transform:translateX(0);visibility:visible}.drawer-heading{display:flex;align-items:center;justify-content:space-between;color:var(--ink);font-size:19px}.drawer-close{height:40px;width:40px;background:var(--soft);border:0;border-radius:8px;font-size:28px;line-height:1}.drawer-group-title{color:#658190;font-size:12px;font-weight:800;letter-spacing:.15em;margin:23px 0 5px}.mobile-drawer>a{color:var(--ink);text-decoration:none;padding:10px;border-radius:6px}.mobile-drawer>a.is-current{background:#E9F8F8;font-weight:800;border-left:3px solid var(--teal)}body.drawer-open{overflow:hidden}.mobile-shortcuts{display:flex;justify-content:space-between;gap:8px;flex-wrap:wrap;padding:24px 0}.mobile-shortcuts a{font-size:13px;text-decoration:none}.cover{gap:22px}.reading-layout{grid-template-columns:1fr}.aside-index{position:static;display:flex;flex-wrap:wrap;gap:10px}.aside-index h3{width:100%}.aside-index a{border:0;padding:5px 9px;background:#EAF1F6}.service-grid{grid-template-columns:1fr}.service-content{order:-1}.service-nav{order:1}}
@media(max-width:760px){.cover,.split,.split--wide,.split--reverse{grid-template-columns:1fr}.cover{padding:36px 0 20px}.cover .media-frame{order:2}.editorial-grid,.exhibition{grid-template-columns:1fr}.exhibition article:nth-child(even){margin-top:0}.section-space{margin-top:44px;margin-bottom:44px}.page-intro{padding:37px 0 25px}.topic-index{gap:0 24px}.reading-steps{grid-template-columns:repeat(2,minmax(0,1fr))}.compare-matrix{grid-template-columns:1fr}.related-list{grid-template-columns:1fr}.footer-grid{grid-template-columns:1fr;gap:18px}.three-columns{grid-template-columns:1fr}.knowledge-block:nth-child(n){transform:none}}
@media(max-width:640px){body{font-size:15px}.container{width:calc(100% - 32px)}h1{font-size:clamp(27px,7.4vw,32px)}.page-intro h1{font-size:clamp(25px,7.1vw,29px)}h2{font-size:clamp(20px,5.6vw,23px)}h3{font-size:18px}.lead{font-size:16px}.topic-index{grid-template-columns:1fr}.section-heading{display:block}.section-space{margin-top:37px;margin-bottom:37px}.soft-panel,.mint-panel,.dark-panel{padding:19px}.media-frame{--media-limit:175px}.media-frame--hero{--media-limit:205px}.media-frame--feature{--media-limit:185px}.media-frame--card{--media-limit:145px}.media-frame--mobile{--media-limit:285px;max-width:250px}.media-frame--banner{--media-limit:135px}.media-frame--hero.media-missing{min-height:145px}.editorial-feature{padding:22px}.reading-steps{gap:14px}.page-section{margin-bottom:30px;padding-bottom:30px}.table-scroll table{font-size:14px}.footer-brand{font-size:19px!important}.footer-brand span{display:block;margin:2px 0 0}.logo-fallback{font-size:13px}.logo-fallback small{font-size:6px}}
@media(max-width:370px){.entry-link{padding:5px 8px;font-size:12px}.brand-logo{max-width:41%}.brand-logo img{max-height:27px}.reading-steps{grid-template-columns:1fr}.mobile-shortcuts{justify-content:flex-start;gap:12px}}
@media(prefers-reduced-motion:reduce){*,*:before,*:after{scroll-behavior:auto!important;animation-duration:.01ms!important;transition-duration:.01ms!important}}
/* Without JavaScript, mobile channel links remain exposed as a readable fallback. */
@media(max-width:920px){html:not(.js-ready) .no-js-nav{display:flex}}