:root{--bg:#F4F7FA;--paper:#fff;--muted:#EAF1F6;--aqua:#E9F8F8;--navy:#102E46;--deep:#163C57;--teal:#087D87;--blue:#237BD3;--heading:#18364B;--text:#344C60;--soft:#64798A;--line:#DCE6ED;--space:clamp(30px,5vw,64px)}
*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:20px}body{margin:0;background:var(--bg);color:var(--text);font-family:Arial,"PingFang SC","Microsoft YaHei",sans-serif;font-size:16px;line-height:1.8;overflow-wrap:break-word}body.drawer-open{overflow:hidden}a{color:#17649a;text-underline-offset:3px}a:hover{color:var(--teal)}a:focus-visible,button:focus-visible,summary:focus-visible{outline:3px solid #13B8C5;outline-offset:3px}button{font:inherit;cursor:pointer}img{max-width:100%}.container{width:min(100% - 56px,1200px);margin-inline:auto}.read-width{max-width:780px}.section{margin-block:var(--space)}.section-tight{margin-block:32px}h1,h2,h3{color:var(--heading);line-height:1.38;letter-spacing:-.018em}h1{font-size:clamp(32px,3.5vw,42px);margin:0 0 20px}h2{font-size:clamp(24px,2.3vw,28px);margin:0 0 18px}h3{font-size:clamp(18px,1.8vw,21px);margin:0 0 12px}p{margin:0 0 1.1em}ul,ol{padding-left:1.5em}li+li{margin-top:8px}strong{color:var(--heading)}.eyebrow{font-size:12px;letter-spacing:.16em;font-weight:700;color:var(--teal);text-transform:uppercase}.lead{font-size:18px;line-height:1.85;color:#405b6e}.small{font-size:14px;color:var(--soft)}.skip-link{position:absolute;z-index:1000;top:-60px;left:15px;background:#fff;padding:10px}.skip-link:focus{top:10px}.site-header{background:#fff;border-bottom:1px solid var(--line)}.brand-bar{display:flex;align-items:center;gap:22px;min-height:72px}.brand{display:flex;align-items:center;gap:12px;color:var(--heading);text-decoration:none;font-weight:900;white-space:nowrap}.brand-text{font-size:13px;letter-spacing:.05em}.brand-summary{font-size:13px;color:var(--soft);margin-right:auto}.register-link,.button{display:inline-flex;align-items:center;justify-content:center;min-height:42px;padding:9px 19px;border-radius:11px;background:var(--deep);color:#fff;font-weight:700;text-decoration:none;white-space:nowrap}.register-link:hover,.button:hover{background:#087d87;color:#fff}.button--light{background:#e3f5f6;color:#0c5360;border:1px solid #abdce0}.button--light:hover{background:#d0eeef;color:#0b3e4b}.desktop-nav{background:var(--navy)}.nav-line{display:flex;justify-content:space-between;gap:6px}.nav-line>a{color:#e6f5fc;flex:1;min-width:0;text-align:center;text-decoration:none;position:relative;padding:11px 8px;font-size:15px;white-space:nowrap}.nav-line>a[aria-current=page]{font-weight:800;color:#fff}.nav-line>a[aria-current=page]:after{content:"";height:3px;width:32px;background:#13B8C5;position:absolute;bottom:0;left:50%;transform:translateX(-50%)}.nav-line>a:hover{background:#1d4762;color:#fff}.menu-toggle,.mobile-drawer,.drawer-overlay,.mobile-quick,.nojs-nav{display:none}.breadcrumb{display:flex;gap:11px;align-items:center;color:var(--soft);font-size:13px;padding-top:26px}.breadcrumb a{text-decoration:none}.page-intro{padding:25px 0 28px;border-bottom:1px solid var(--line)}.page-intro p{max-width:820px;margin:0}.page-kicker{margin-bottom:9px}.section-nav{display:flex;flex-wrap:wrap;gap:10px;padding-block:20px;border-bottom:1px solid var(--line)}.section-nav a{padding:7px 14px;background:#fff;border:1px solid var(--line);border-radius:30px;text-decoration:none;font-size:14px}.hero{display:grid;grid-template-columns:minmax(0,1.08fr) minmax(0,1fr);align-items:center;gap:clamp(20px,4vw,52px);padding:42px 0 8px}.hero p{max-width:590px}.hero-actions{display:flex;flex-wrap:wrap;gap:12px;margin-top:25px}.media-frame{display:flex;align-items:center;justify-content:center;min-width:0;width:100%;padding:8px;border-radius:14px;background:var(--muted)}.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--article{--media-limit:220px}.media-frame--card{--media-limit:185px}.media-frame--wide{--media-limit:210px}.media-frame--mobile{--media-limit:350px;max-width:320px}.media-frame--logo{width:auto;background:transparent;padding:0;--media-limit:38px;border-radius:0;min-width:0}.media-frame--logo img{max-width:180px}.media-placeholder{display:flex;align-items:center;justify-content:center;background:linear-gradient(145deg,#eaf1f6,#f5fbfc);color:#668091;font-size:13px;border:1px dashed #c9dce5;border-radius:9px;width:100%;min-height:90px;max-height:150px;padding:20px;text-align:center}.media-frame--logo .media-placeholder{min-height:30px;max-height:38px;width:120px;padding:0}.topic-directory{display:grid;grid-template-columns:1fr 1fr;column-gap:45px;row-gap:0;border-top:2px solid var(--navy)}.topic-directory article{padding:19px 0;border-bottom:1px solid var(--line)}.topic-directory .topic-number{float:right;color:#96aab8;font-size:13px;font-weight:700}.topic-directory h3{margin:0 0 7px}.topic-directory p{margin:0 0 8px;font-size:15px}.topic-directory a{font-weight:700}.feature-focus{display:grid;grid-template-columns:minmax(0,2fr) minmax(0,1fr);gap:22px}.focus-main{background:#fff;border-left:4px solid var(--teal);padding:28px;border-radius:0 12px 12px 0}.focus-side{display:flex;flex-direction:column;gap:14px}.focus-side article{background:var(--muted);padding:20px;border-radius:12px;flex:1}.feature-split,.image-text{display:grid;grid-template-columns:minmax(0,.9fr) minmax(0,1.1fr);gap:38px;align-items:center}.feature-split.reverse{grid-template-columns:minmax(0,1.15fr) minmax(0,.85fr)}.feature-split.reverse .feature-image{order:2}.tone-band{background:var(--deep);color:#e6f2f8;padding:clamp(26px,4vw,48px);border-radius:14px}.tone-band h2,.tone-band h3,.tone-band strong{color:#fff}.tone-band a{color:#95edf1}.rule-tiles{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:20px;align-items:start}.rule-tiles article{padding:23px;background:white;border:1px solid var(--line);border-radius:12px}.rule-tiles article:nth-child(2){margin-top:25px;background:var(--aqua)}.rule-tiles article:nth-child(3){margin-top:50px}.reading-steps{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:2px;background:var(--line);border:1px solid var(--line);border-radius:12px;overflow:hidden}.reading-steps article{background:white;padding:23px}.step-num{display:block;font-size:28px;line-height:1.2;font-weight:800;color:#138d99;margin-bottom:8px}.reading-steps p{font-size:14px}.editor-note{padding:22px 28px;background:#e6eff5;border-left:3px solid #237bd3;border-radius:0 12px 12px 0}.editor-note p:last-child{margin-bottom:0}.chapter-grid{display:grid;grid-template-columns:minmax(0,1fr) 255px;gap:55px;align-items:start}.fact-rail{padding:24px;background:#e5eff4;border-radius:12px}.fact-rail p{font-size:14px;border-bottom:1px solid #cddde6;padding-bottom:12px}.fact-rail p:last-child{border-bottom:0}.flow-steps{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:12px;margin:24px 0}.flow-steps article{border-top:4px solid #13B8C5;background:#fff;padding:19px;border-radius:5px 5px 10px 10px}.flow-steps span{font-size:14px;color:var(--teal);font-weight:800}.table-scroll{max-width:100%;overflow-x:auto;overscroll-behavior-x:contain;margin:25px 0;border:1px solid var(--line);border-radius:12px;background:#fff}.data-table{width:100%;border-collapse:collapse;min-width:590px;text-align:left;line-height:1.65}.data-table caption{text-align:left;font-weight:800;padding:15px 18px;color:var(--heading)}.data-table th,.data-table td{padding:13px 17px;border-top:1px solid var(--line);vertical-align:top}.data-table th{background:#eaf1f6;color:#18364b}.data-table tbody tr:nth-child(even){background:#f8fbfc}.article-block{margin-bottom:35px}.article-block p{max-width:800px}.article-block h3{margin-top:23px}.callout{padding:20px 23px;background:var(--aqua);border-left:3px solid #13b8c5;border-radius:0 12px 12px 0}.number-stack{counter-reset:steps;display:grid;gap:15px}.number-stack article{counter-increment:steps;position:relative;padding:18px 20px 18px 70px;border-bottom:1px solid var(--line);background:#fff;border-radius:8px}.number-stack article:before{content:counter(steps,decimal-leading-zero);position:absolute;left:20px;top:18px;font-weight:800;font-size:20px;color:var(--teal)}.matrix{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:16px}.matrix article{padding:24px;background:#fff;border-top:4px solid #237BD3;border-radius:10px}.exhibit{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:30px}.exhibit article{background:#fff;padding:20px;border:1px solid var(--line);border-radius:12px}.exhibit article:nth-child(2){margin-top:44px}.exhibit .media-frame{margin-bottom:20px}.rule-layout{display:grid;grid-template-columns:210px minmax(0,1fr);gap:48px}.rule-aside{align-self:start;position:sticky;top:20px;background:#eaf1f6;padding:21px;border-radius:12px}.rule-aside a,.service-nav a{display:block;padding:8px 0;text-decoration:none}.rule-content>section{padding-bottom:28px;border-bottom:1px solid var(--line);margin-bottom:35px}.faq-list{display:grid;gap:9px;margin-top:20px}.faq-list details{background:#fff;border:1px solid var(--line);border-radius:10px;padding:0 19px}.faq-list summary{cursor:pointer;font-weight:700;color:var(--heading);padding:14px 0}.faq-list p{padding-bottom:15px;margin:0}.service-layout{display:grid;grid-template-columns:235px minmax(0,1fr);gap:45px}.service-nav{background:var(--muted);padding:23px;border-radius:12px;align-self:start}.service-main>section{margin-bottom:37px}.related{border-top:1px solid var(--line);padding-top:22px;margin-top:35px}.related a{margin-right:16px;display:inline-block}.site-footer{background:#0B2539;color:#DCECF5;padding:45px 0 20px;margin-top:60px}.footer-layout{display:grid;grid-template-columns:1.5fr 1fr;gap:42px}.footer-brand{font-size:19px;color:#fff}.footer-note{font-size:13px;max-width:650px;color:#bcd1df}.site-footer nav{display:grid;grid-template-columns:1fr 1fr;align-content:start;gap:8px 17px}.site-footer a{color:#dcecf5;text-decoration:none}.site-footer a:hover{color:#70e3e9}.footer-bottom{margin-top:24px;padding-top:15px;border-top:1px solid #325268;font-size:12px;color:#aec4d0}.back-top{position:fixed;bottom:22px;right:22px;background:var(--navy);color:white;border:0;border-radius:50%;width:42px;height:42px;z-index:20}.back-top[hidden]{display:none}
@media(max-width:1024px){.container{width:min(100% - 44px,1200px)}.brand-summary{display:none}.brand{margin-right:auto}.chapter-grid{gap:25px}.feature-split{gap:25px}}
@media(max-width:920px){.brand-bar{min-height:62px;display:grid;grid-template-columns:40px minmax(0,1fr) auto;gap:10px}.brand{justify-self:center;margin:0;min-width:0}.brand-text{display:none}.media-frame--logo{--media-limit:30px}.media-frame--logo img{max-width:135px}.register-link{font-size:12px;min-height:39px;padding:7px 12px}.desktop-nav{display:none}.menu-toggle{display:flex;flex-direction:column;gap:5px;justify-content:center;align-items:center;width:40px;height:40px;border:1px solid var(--line);border-radius:9px;background:white}.menu-toggle span{height:2px;background:var(--navy);width:19px}.drawer-overlay{display:block;position:fixed;inset:0;background:rgba(5,25,39,.55);z-index:200;opacity:0;visibility:hidden;pointer-events:none;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:white;z-index:201;transform:translateX(-102%);visibility:hidden;pointer-events:none;overflow-y:auto;transition:transform .22s,visibility .22s;box-shadow:3px 0 20px rgba(0,0,0,.12)}.mobile-drawer.is-open{transform:translateX(0);visibility:visible;pointer-events:auto}.drawer-head{display:flex;justify-content:space-between;align-items:center;padding:14px 18px;border-bottom:1px solid var(--line)}.drawer-close{font-size:27px;line-height:1;border:0;background:none;width:42px;height:42px}.mobile-drawer nav{padding:8px 22px 30px;display:flex;flex-direction:column}.mobile-drawer nav a{padding:11px 8px;border-bottom:1px solid var(--line);text-decoration:none;color:var(--heading)}.mobile-drawer nav a[aria-current=page]{font-weight:800;border-left:3px solid var(--teal);padding-left:12px}.drawer-heading{color:var(--teal);font-size:12px;font-weight:800;letter-spacing:.12em;margin-top:23px}.mobile-quick{display:flex;flex-wrap:wrap;justify-content:space-between;gap:14px;padding:22px 0 0}.mobile-quick a{font-size:14px}.nojs-nav{display:flex;overflow-x:auto;gap:12px;white-space:nowrap;padding:10px 20px;background:#eaf1f6}.nojs-nav a{color:var(--navy);font-size:14px}.nojs-nav a[aria-current=page]{font-weight:800}}
@media(max-width:760px){.hero,.feature-focus,.feature-split,.feature-split.reverse,.chapter-grid,.exhibit,.rule-layout,.service-layout,.footer-layout,.image-text{grid-template-columns:minmax(0,1fr)}.feature-split.reverse .feature-image{order:0}.rule-aside{position:static}.service-main{order:0}.service-nav{order:1}.matrix{grid-template-columns:1fr}.flow-steps,.reading-steps{grid-template-columns:1fr 1fr}.rule-tiles{grid-template-columns:1fr 1fr}.rule-tiles article:nth-child(n){margin-top:0}.exhibit article:nth-child(2){margin-top:0}.hero{padding-top:25px}.footer-layout{gap:10px}}
@media(max-width:640px){.container{width:calc(100% - 32px)}body{font-size:15px;line-height:1.78}h1{font-size:clamp(27px,7vw,32px)}h2{font-size:clamp(20px,5.5vw,23px)}h3{font-size:18px}.lead{font-size:16px}.topic-directory,.rule-tiles,.reading-steps,.flow-steps{grid-template-columns:1fr}.rule-tiles article:nth-child(n){margin-top:0}.media-frame--hero{--media-limit:205px}.media-frame--feature{--media-limit:185px}.media-frame--article{--media-limit:175px}.media-frame--card{--media-limit:145px}.media-frame--wide{--media-limit:135px}.media-frame--mobile{--media-limit:285px;max-width:250px}.section{margin-block:35px}.focus-main{padding:21px}.tone-band{padding:23px}.page-intro{padding-top:22px}.breadcrumb{padding-top:16px}.hero-actions a{flex:1}.site-footer{margin-top:38px}.media-frame--logo .media-placeholder{width:85px;font-size:10px}.brand-bar{gap:6px}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*,*:before,*:after{animation-duration:.01ms!important;transition-duration:.01ms!important}}