:root{--bg:#F4F7FA;--paper:#fff;--pale:#EAF1F6;--tint:#E9F8F8;--nav:#102E46;--deep:#163C57;--cyan:#13B8C5;--blue:#237BD3;--head:#18364B;--ink:#344C60;--muted:#64798A;--line:#DCE6ED;--footer:#0B2539;--footer-ink:#DCECF5;--space:clamp(30px,5vw,64px)}
*,*::before,*::after{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:25px}body{margin:0;background:var(--bg);color:var(--ink);font:16px/1.8 Arial,'PingFang SC','Microsoft YaHei',sans-serif;overflow-x:hidden}img{max-width:100%}a{color:#1765a5;text-decoration-thickness:1px;text-underline-offset:4px}a:hover{color:#096379}button{font:inherit}p{margin:0 0 1.1em}h1,h2,h3{color:var(--head);line-height:1.36;letter-spacing:-.018em;margin:0 0 .65em}h1{font-size:clamp(29px,3vw,43px)}h2{font-size:clamp(22px,2.1vw,28px)}h3{font-size:19px}ul,ol{padding-left:1.4em}li{margin:.36em 0}strong{color:#244455}section[id],article[id],h2[id]{scroll-margin-top:22px}:focus-visible{outline:3px solid var(--cyan);outline-offset:3px}.container{width:min(100% - 56px,1200px);margin-inline:auto}.reader{max-width:790px}.section-space{margin-block:var(--space)}.section-kicker{color:#167e8b;text-transform:uppercase;letter-spacing:.13em;font-weight:700;font-size:12px;margin-bottom:14px}.muted{color:var(--muted)}.eyebrow{font-size:13px;font-weight:700;color:#117a88;letter-spacing:.14em;text-transform:uppercase}.lead{font-size:17px;line-height:1.85;color:#475f73;max-width:790px}.small-print{font-size:13px}.skip-link{position:absolute;left:15px;top:-80px;padding:10px;background:white;z-index:100}.skip-link:focus{top:12px}
.brand-bar{background:white;border-bottom:1px solid var(--line)}.brand-inner{height:72px;display:flex;align-items:center;gap:24px}.brand-logo{display:inline-flex;align-items:center;text-decoration:none;min-width:0}.brand-logo .media-frame{background:none;padding:0;border:0;margin:0;display:flex}.brand-logo img{max-height:38px;width:auto;max-width:210px}.brand-wordmark{font-size:25px;color:var(--head);font-weight:800;white-space:nowrap}.brand-wordmark small{display:block;font-size:9px;letter-spacing:.18em;line-height:1}.brand-tagline{color:#577083;font-size:13px;white-space:nowrap}.entry-link{margin-left:auto;white-space:nowrap;background:var(--deep);color:#fff;border-radius:7px;padding:9px 21px;font-size:14px;font-weight:700;text-decoration:none}.entry-link:hover{background:#13556c;color:white}.desktop-nav{background:var(--nav)}.nav-inner{min-height:50px;display:flex;align-items:stretch;justify-content:space-between;gap:6px}.nav-inner a{display:flex;align-items:center;justify-content:center;white-space:nowrap;padding:8px 10px;border-bottom:3px solid transparent;color:#ecf6fb;font-size:14px;text-decoration:none;font-weight:600}.nav-inner a:hover{color:white;background:#214861}.nav-inner a.is-active{border-bottom-color:var(--cyan);font-weight:800;background:#1d435b}.menu-button{display:none}.mobile-drawer,.drawer-overlay{display:none}.nojs-nav{display:none}
.page-intro{padding:44px 0 26px}.page-intro h1{max-width:950px;font-size:clamp(27px,2.7vw,36px)}.breadcrumbs{display:flex;gap:12px;align-items:center;font-size:13px;color:var(--muted);margin-bottom:15px}.breadcrumbs a{color:#39708e;text-decoration:none}.intro-band{background:#fff;border-bottom:1px solid var(--line)}.cover{background:#fff;padding:54px 0 46px}.cover-grid{display:grid;grid-template-columns:minmax(0,1.06fr) minmax(0,.94fr);align-items:center;gap:40px}.cover h1{max-width:620px}.cover p{max-width:605px}.cover-actions,.link-row{display:flex;gap:12px;flex-wrap:wrap;margin-top:22px}.button-link{display:inline-flex;align-items:center;justify-content:center;padding:10px 18px;border-radius:8px;text-decoration:none;background:var(--nav);color:white;font-weight:700;font-size:14px}.button-link:hover{color:white;background:#176a83}.button-link.secondary{background:var(--tint);color:#176179}.media-frame{width:100%;min-width:0;display:flex;align-items:center;justify-content:center;background:var(--pale);border-radius:14px;padding:10px;margin:0;--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--logo{--media-limit:38px}.media-frame--hero{--media-limit:310px}.media-frame--feature{--media-limit:250px}.media-frame--card{--media-limit:185px}.media-frame--wide{--media-limit:210px}.media-frame--mobile{--media-limit:350px;max-width:320px;margin:auto}.media-placeholder{min-height:105px;color:#648196;border:1px dashed #bfd2df;text-align:center;font-size:13px}.media-placeholder span{padding:12px}.media-frame--hero.media-placeholder{min-height:195px}.media-frame--logo.media-placeholder{min-height:0}.split{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:35px;align-items:center}.split--uneven{grid-template-columns:minmax(0,1.35fr) minmax(0,.65fr)}.split--aside{grid-template-columns:minmax(0,2fr) minmax(220px,1fr);align-items:start}.editor-index{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:0 50px;border-top:1px solid var(--line)}.index-item{border-bottom:1px solid var(--line);padding:24px 0}.index-item h3{margin:0 0 6px}.index-item p{margin:0 0 7px;font-size:15px}.index-item a{text-decoration:none;font-weight:700}.feature-story{background:white;padding:28px;border:1px solid var(--line);border-left:4px solid var(--cyan);border-radius:10px}.mini-story{padding:18px 0;border-bottom:1px solid var(--line)}.mini-story:first-child{padding-top:0}.mini-story h3{margin-bottom:7px}.mini-story p{font-size:15px}.dark-band{background:var(--deep);color:#e2f0f5;padding:40px;border-radius:14px}.dark-band h2,.dark-band h3{color:white}.dark-band p{color:#d9e8ef}.pale-band{padding:32px;background:var(--tint);border-radius:12px}.section-heading{display:flex;align-items:end;justify-content:space-between;gap:22px;margin-bottom:25px;border-bottom:1px solid var(--line);padding-bottom:10px}.section-heading h2{margin:0}.topic-list{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:18px}.topic-box{background:white;border:1px solid var(--line);border-radius:12px;padding:22px}.topic-box p{font-size:15px}.topic-box h3{margin-bottom:8px}.route-steps{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:15px;counter-reset:route}.route-step{padding:21px 15px;border-top:3px solid #1597a6;background:white;counter-increment:route}.route-step::before{content:'0' counter(route);display:block;font-size:23px;font-weight:800;color:#1597a6}.route-step p{font-size:14px}.note{border-left:3px solid var(--cyan);padding:13px 17px;background:#e9f8f8;border-radius:0 8px 8px 0}.note p:last-child{margin-bottom:0}.article-block{margin-block:36px}.article-block p{max-width:790px}.article-block h2{margin-bottom:17px}.article-block h3{margin:24px 0 10px}.reading-layout{display:grid;grid-template-columns:minmax(0,1fr) 260px;gap:40px;align-items:start}.side-facts{background:#EAF1F6;padding:24px;border-radius:12px;border:1px solid var(--line)}.side-facts h2{font-size:21px}.side-facts li{font-size:14px}.wide-table{overflow-x:auto;max-width:100%;background:white;border:1px solid var(--line);border-radius:10px}.wide-table table{border-collapse:collapse;width:100%;min-width:590px;font-size:15px}.wide-table caption{text-align:left;padding:17px 20px 5px;font-weight:700;color:var(--head)}.wide-table th,.wide-table td{text-align:left;padding:13px 17px;border-bottom:1px solid var(--line);vertical-align:top}.wide-table th{background:#e9f1f5;color:var(--head)}.wide-table tr:last-child td{border-bottom:0}.anchor-nav{display:flex;flex-wrap:wrap;gap:10px;margin:23px 0}.anchor-nav a{background:#e7f2f6;border:1px solid #cadddf;border-radius:7px;padding:9px 14px;text-decoration:none;font-size:14px;font-weight:700}.numbered{counter-reset:step}.numbered-item{counter-increment:step;position:relative;padding:5px 0 15px 55px;border-left:2px solid #a1d5db;margin-left:16px}.numbered-item::before{content:counter(step);position:absolute;left:-18px;top:0;width:34px;height:34px;border-radius:50%;display:grid;place-items:center;background:var(--deep);color:white;font-weight:700}.numbered-item:last-child{border-left-color:transparent}.numbered-item h3{margin:0 0 8px}.numbered-item p{margin-bottom:8px}.gallery-grid{display:grid;grid-template-columns:1.15fr .85fr;gap:25px}.gallery-panel{background:white;border:1px solid var(--line);border-radius:13px;padding:20px}.gallery-panel h3{margin:16px 0 8px}.gallery-panel p{font-size:15px}.gallery-panel:nth-child(2){margin-top:45px}.gallery-panel:nth-child(3){margin-top:-30px}.faq-list{display:grid;gap:10px}.faq-item{background:#fff;border:1px solid var(--line);border-radius:9px;padding:0 20px}.faq-item summary{cursor:pointer;color:var(--head);font-weight:700;padding:15px 10px 15px 0}.faq-item summary:hover{color:#16768a}.faq-answer{border-top:1px solid var(--line);padding:12px 0 3px;font-size:15px}.related{padding-top:25px;border-top:1px solid var(--line)}.related-links{display:flex;flex-wrap:wrap;gap:12px}.related-links a{background:white;border:1px solid var(--line);padding:13px 18px;border-radius:7px;text-decoration:none;font-weight:700}.related-links a:hover{border-color:#3ba6bd}.statement{font-size:14px;color:#526d7f;border-top:1px solid var(--line);padding-top:20px}.service-layout{display:grid;grid-template-columns:235px minmax(0,1fr);gap:45px;align-items:start}.service-nav{position:sticky;top:18px;background:var(--pale);padding:20px;border-radius:10px}.service-nav a{display:block;padding:9px 0;text-decoration:none;font-size:14px;border-bottom:1px solid #cfdee7}.service-main section{margin-bottom:40px}.service-main section h2{padding-bottom:10px;border-bottom:1px solid var(--line)}.mobile-quick{display:none}.site-footer{margin-top:72px;background:var(--footer);color:var(--footer-ink);padding:42px 0 18px}.footer-grid{display:grid;grid-template-columns:2fr 1fr 1fr;gap:45px}.footer-grid p{font-size:14px;max-width:410px}.footer-grid h2{color:white;font-size:16px}.footer-grid a:not(.footer-brand){display:block;color:var(--footer-ink);font-size:14px;margin-bottom:8px;text-decoration:none}.footer-grid a:hover{color:white;text-decoration:underline}.footer-brand{color:white;font-size:23px;font-weight:800;text-decoration:none}.footer-brand span{display:block;font-size:10px;letter-spacing:.13em}.footer-bottom{border-top:1px solid #355263;padding-top:18px;margin-top:28px;display:flex;justify-content:space-between;gap:10px;font-size:12px;color:#b8d3de}.back-top{position:fixed;right:22px;bottom:22px;width:44px;height:44px;background:var(--nav);color:#fff;border:0;border-radius:9px;cursor:pointer;opacity:0;visibility:hidden;pointer-events:none;transition:opacity .15s}.back-top.is-visible{opacity:1;visibility:visible;pointer-events:auto}
@media(max-width:1200px){.container{width:min(100% - 44px,1200px)}.nav-inner a{padding-inline:7px}.cover-grid{gap:24px}}
@media(max-width:920px){.container{width:calc(100% - 44px)}.brand-inner{height:63px;justify-content:space-between;gap:8px;position:relative}.brand-logo{position:absolute;left:50%;transform:translateX(-50%);max-width:calc(100% - 185px);justify-content:center}.brand-logo img{max-height:30px;max-width:100%}.brand-wordmark{font-size:19px}.brand-wordmark small{font-size:7px}.brand-tagline,.desktop-nav{display:none}.menu-button{display:flex;width:40px;height:40px;align-items:center;justify-content:center;flex-direction:column;gap:5px;background:transparent;border:1px solid var(--line);border-radius:7px;cursor:pointer}.menu-button span{width:19px;height:2px;background:var(--nav)}.entry-link{margin-left:auto;font-size:12px;padding:8px 10px;min-height:38px;display:grid;place-items:center}.mobile-drawer{display:block;position:fixed;z-index:1002;inset:0 auto 0 0;width:min(86vw,340px);background:white;box-shadow:4px 0 35px #0015;transform:translateX(-105%);transition:transform .22s ease;visibility:hidden;overflow-y:auto}.mobile-drawer.is-open{transform:translateX(0);visibility:visible}.drawer-overlay{display:block;position:fixed;inset:0;background:rgba(7,27,40,.55);z-index:1001;opacity:0;visibility:hidden;pointer-events:none;transition:opacity .2s}.drawer-overlay.is-visible{opacity:1;visibility:visible;pointer-events:auto}.drawer-heading{display:flex;align-items:center;justify-content:space-between;border-bottom:1px solid var(--line);padding:14px 20px;font-size:18px;font-weight:800;color:var(--head)}.drawer-close{width:40px;height:40px;border:1px solid var(--line);background:var(--pale);border-radius:7px;font-size:25px;line-height:1;cursor:pointer}.drawer-group{padding:15px 22px 4px}.drawer-group p{font-size:12px;font-weight:800;color:#6c8495;letter-spacing:.12em;margin:0 0 6px}.drawer-group a{display:block;padding:10px 12px;border-radius:7px;color:var(--ink);text-decoration:none;font-weight:650}.drawer-group a.is-active{background:#dff4f5;border-left:3px solid var(--cyan)}body.menu-open{overflow:hidden}.nojs-nav{display:flex;flex-wrap:wrap;gap:7px;padding-block:12px}.nojs-nav a{font-size:13px;padding:4px 8px;background:white}.mobile-quick{display:flex;justify-content:center;gap:12px;flex-wrap:wrap;padding:20px 0 0;border-top:1px solid var(--line)}.mobile-quick a{font-size:13px;text-decoration:none}.footer-grid{gap:25px}}
@media(max-width:760px){.split,.split--uneven,.split--aside,.reading-layout,.service-layout,.gallery-grid{grid-template-columns:minmax(0,1fr)}.cover-grid{grid-template-columns:1fr}.cover-grid .media-frame{grid-row:2}.gallery-panel:nth-child(2),.gallery-panel:nth-child(3){margin-top:0}.service-nav{position:static;order:2}.service-main{order:1}.topic-list{grid-template-columns:1fr 1fr}.route-steps{grid-template-columns:repeat(2,minmax(0,1fr))}.footer-grid{grid-template-columns:2fr 1fr}.footer-grid>div:last-child{grid-column:2}.cover{padding:36px 0}.page-intro{padding:32px 0 18px}}
@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:15px}.editor-index,.topic-list{grid-template-columns:1fr}.section-heading{display:block}.index-item{padding:18px 0}.feature-story{padding:20px}.dark-band,.pale-band{padding:23px 18px}.cover-grid{gap:22px}.media-frame{padding:8px}.media-frame--logo{--media-limit:30px}.media-frame--hero{--media-limit:205px}.media-frame--feature{--media-limit:185px}.media-frame--card{--media-limit:145px}.media-frame--wide{--media-limit:135px}.media-frame--mobile{--media-limit:285px;max-width:250px}.footer-grid{grid-template-columns:1fr 1fr;gap:20px}.footer-grid>div:first-child{grid-column:span 2}.footer-grid>div:last-child{grid-column:auto}.footer-bottom{flex-direction:column}.site-footer{margin-top:45px}.route-steps{gap:9px}.route-step{padding:14px 10px}.brand-logo{max-width:calc(100% - 168px)}.entry-link{font-size:12px;padding:7px 9px}.back-top{right:12px;bottom:12px}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*,*::before,*::after{transition-duration:.01ms!important;animation-duration:.01ms!important}}