:root{--bg:#F4F7FA;--white:#fff;--pale:#EAF1F6;--mint:#E9F8F8;--nav:#102E46;--deep:#163C57;--cyan:#13B8C5;--blue:#237BD3;--ink:#18364B;--body:#344C60;--sub:#64798A;--line:#DCE6ED;--footer:#0B2539;--space:clamp(30px,4.3vw,64px)}
*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:26px}body{margin:0;overflow-x:hidden;background:var(--bg);color:var(--body);font:16px/1.8 Arial,"PingFang SC","Microsoft YaHei",sans-serif}body.drawer-open{overflow:hidden}a{color:#12649f;text-decoration:none}a:hover{text-decoration:underline}a:focus-visible,button:focus-visible,summary:focus-visible{outline:3px solid var(--cyan);outline-offset:3px}img{max-width:100%}h1,h2,h3,h4{color:var(--ink);line-height:1.38;margin:0 0 .7em}h1{font-size:clamp(32px,3vw,36px)}h2{font-size:clamp(23px,2.35vw,28px)}h3{font-size:clamp(18px,1.65vw,21px)}p{margin:.55em 0 1.25em}ul,ol{padding-left:1.45em}li+li{margin-top:.45em}strong{color:var(--ink)}.shell{width:min(1200px,calc(100% - 56px));margin-inline:auto}.reading{max-width:780px}.wide-reading{max-width:960px}.section{margin-block:var(--space)}.section-pad{padding-block:var(--space)}.eyebrow{font-size:13px;font-weight:700;letter-spacing:.14em;color:#157a93;text-transform:uppercase;margin-bottom:12px}.lead{font-size:18px;color:#415c70;line-height:1.82}.muted,.caption{color:var(--sub);font-size:14px}.rule{border:0;border-top:1px solid var(--line);margin:32px 0}.panel{padding:26px;background:#fff;border:1px solid var(--line);border-radius:14px}.soft-panel{background:var(--pale);border-radius:14px;padding:clamp(20px,3vw,34px)}.mint-panel{background:var(--mint);padding:24px;border-radius:14px}.dark-panel{background:var(--deep);color:#e8f6fc;padding:clamp(25px,4vw,45px);border-radius:14px}.dark-panel h2,.dark-panel h3,.dark-panel strong{color:#fff}.dark-panel a{color:#8fe8f0}.tag{display:inline-block;font-size:12px;letter-spacing:.05em;color:#14617b;background:#def4f6;padding:2px 9px;border-radius:99px}.btn,.text-button{display:inline-flex;align-items:center;justify-content:center;min-height:44px;padding:9px 19px;border-radius:8px;font-weight:700}.btn{background:var(--nav);color:#fff}.btn:hover{background:#1e516e;color:#fff;text-decoration:none}.text-button{border:1px solid #a3c2d4;color:var(--ink)}.text-button:hover{background:#eaf3f7;text-decoration:none}.button-row{display:flex;gap:12px;flex-wrap:wrap;margin-top:23px}.section-heading{display:flex;align-items:baseline;gap:18px;justify-content:space-between;border-bottom:2px solid var(--ink);padding-bottom:12px;margin-bottom:25px}.section-heading>*{margin:0}.section-heading small{color:var(--sub)}
/* Header */
.skip-link{position:absolute;top:-100px;left:12px;z-index:60;background:#fff;padding:8px}.skip-link:focus{top:8px}.brand-bar{background:#fff}.brand-inner{height:72px;display:flex;align-items:center;gap:18px}.brand{display:flex;align-items:center;min-width:0;gap:10px;color:var(--nav);font-weight:800;white-space:nowrap}.brand:hover{text-decoration:none}.brand .media-frame{background:transparent;padding:0;border:0;border-radius:0;min-height:0}.brand .media-frame img{max-height:38px}.brand-name{font-size:21px}.brand-caption{font-size:13px;color:var(--sub);margin-right:auto;white-space:nowrap}.join-link{display:flex;align-items:center;justify-content:center;background:var(--cyan);color:#052e3e;border-radius:7px;font-size:14px;font-weight:800;min-height:42px;padding:0 20px;white-space:nowrap}.join-link:hover{background:#0aa5b4;text-decoration:none}.desktop-nav{background:var(--nav)}.nav-row{display:flex;min-height:50px;align-items:stretch;justify-content:space-between;gap:4px}.nav-row a{display:flex;position:relative;align-items:center;justify-content:center;flex:1;min-width:0;white-space:nowrap;padding:8px 5px;font-size:14px;color:#deedf5;font-weight:500}.nav-row a:hover{background:#23465f;text-decoration:none}.nav-row a[aria-current]{font-weight:800;color:#fff}.nav-row a[aria-current]:after{position:absolute;content:"";height:3px;width:33px;bottom:0;left:50%;transform:translateX(-50%);background:var(--cyan)}.menu-toggle,.mobile-drawer,.drawer-overlay,.quick-links{display:none}.nojs-nav{display:flex;gap:14px;flex-wrap:wrap;padding-block:12px}
/* media */
.media-frame{display:flex;align-items:center;justify-content:center;min-width:0;width:100%;margin:0;padding:8px;background:var(--pale);border-radius:14px}.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-frame--logo{background:transparent;padding:0;--media-limit:38px;justify-content:flex-start;width:auto;max-width:175px}.media-frame--missing{min-height:110px;border:1px dashed #bcced9;font-size:13px;color:var(--sub)}.media-frame--hero.media-frame--missing{min-height:205px}.media-frame--logo.media-frame--missing{min-height:29px;min-width:70px;max-width:110px;font-size:10px}
/* page framework */
.page-intro{padding:43px 0 24px}.page-intro p{max-width:810px}.breadcrumbs{font-size:13px;color:var(--sub);margin-bottom:19px}.breadcrumbs a{color:var(--sub)}.article-section{margin:40px 0}.article-section h2{padding-top:3px}.article-section h3{margin-top:28px}.anchor-nav{display:flex;gap:9px;flex-wrap:wrap;margin:16px 0 32px}.anchor-nav a{border:1px solid var(--line);border-radius:999px;padding:8px 17px;background:#fff;color:var(--ink);font-size:14px}.anchor-nav a:hover{border-color:var(--cyan);text-decoration:none}.two-col{display:grid;grid-template-columns:1fr 1fr;gap:32px;align-items:start}.two-col>*{min-width:0}.two-col--wide{grid-template-columns:minmax(0,1.4fr) minmax(0,1fr)}.three-col{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:20px}.editor-grid{display:grid;grid-template-columns:minmax(0,2fr) minmax(0,1fr);gap:25px}.vertical-stack{display:grid;gap:18px}.feature-strip{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1.2fr);gap:33px;align-items:center}.feature-strip>*{min-width:0}.related{border-top:2px solid var(--ink);padding-top:24px;margin-block:45px 60px}.related-links{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:12px}.related-links a{padding:18px 17px;background:white;border:1px solid var(--line);border-radius:10px;display:flex;justify-content:space-between;gap:7px;line-height:1.5}.related-links a:hover{text-decoration:none;border-color:var(--cyan)}.number-steps{counter-reset:step;list-style:none;padding:0;display:grid;gap:13px}.number-steps li{counter-increment:step;display:grid;grid-template-columns:40px 1fr;gap:15px;align-items:start;margin:0;padding:15px 0;border-top:1px solid var(--line)}.number-steps li:before{content:counter(step,decimal-leading-zero);font-size:24px;line-height:1.3;font-weight:800;color:#0b899c}.number-steps strong{display:block;margin-bottom:3px}.table-scroll{overflow-x:auto;max-width:100%;border:1px solid var(--line);border-radius:12px;background:white}.data-table{width:100%;min-width:580px;border-collapse:collapse;font-size:15px;line-height:1.65}.data-table caption{text-align:left;font-weight:700;color:var(--ink);padding:12px 16px}.data-table th{background:#eaf1f6;color:var(--ink);text-align:left}.data-table th,.data-table td{padding:13px 16px;border-bottom:1px solid var(--line);vertical-align:top}.data-table tr:last-child td{border-bottom:0}.note{border-left:4px solid var(--cyan);background:var(--mint);padding:18px 22px;margin:23px 0}.faq-list details{background:#fff;border:1px solid var(--line);border-radius:9px;margin:10px 0;overflow:hidden}.faq-list summary{padding:14px 19px;font-weight:700;color:var(--ink);cursor:pointer}.faq-list details[open] summary{background:#eaf1f6}.faq-list details p{padding:5px 19px 17px;margin:0}.index-list{display:grid;grid-template-columns:1fr 1fr;gap:0 30px}.index-list article{padding:19px 0;border-top:1px solid var(--line)}.index-list h3{margin:4px 0 7px}.index-list p{margin:0 0 9px}.focus-main{padding:30px;background:var(--deep);color:#e2f3fb;border-radius:14px}.focus-main h3,.focus-main h2{color:#fff}.focus-main a{color:#83eef1}.mini-article{padding:22px;background:white;border:1px solid var(--line);border-radius:12px}.mini-article h3{margin-bottom:8px}.timeline{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:0}.timeline article{border-top:3px solid var(--cyan);padding:15px 17px;background:white}.timeline article+article{border-left:1px solid var(--line)}.timeline b{font-size:12px;color:#007f95}.timeline h3{margin:7px 0}.timeline p{font-size:14px}.quote{border-left:5px solid var(--cyan);margin:30px 0;padding:10px 24px;color:var(--deep);background:var(--mint);font-size:19px;font-weight:700}.aside-card{padding:22px;background:var(--mint);border-radius:12px}.service-layout{display:grid;grid-template-columns:minmax(205px, .65fr) minmax(0,2fr);gap:40px}.service-menu{background:var(--pale);padding:22px;border-radius:12px;align-self:start}.service-menu a{display:block;padding:6px 0}.gallery{display:grid;grid-template-columns:1.1fr .9fr;gap:25px;align-items:start}.gallery .gallery-card:nth-child(2){margin-top:48px}.gallery-card{background:#fff;padding:18px;border:1px solid var(--line);border-radius:14px}.gallery-card h3{margin-top:14px}.gallery-card p{margin-bottom:3px}
/* footer */
.site-footer{background:var(--footer);color:#dcecf5;padding:42px 0 20px;font-size:14px}.footer-grid{display:grid;grid-template-columns:2fr 1fr;gap:50px}.footer-grid strong{color:#fff}.footer-grid p{max-width:670px;color:#dcecf5}.footer-grid nav{display:grid;grid-template-columns:1fr 1fr;gap:6px 15px;margin-top:12px}.footer-grid a{color:#e5f7fd}.footer-brand{display:flex;align-items:center;gap:10px}.footer-brand img{max-height:31px}.footer-bottom{border-top:1px solid #355165;margin-top:26px;padding-top:16px;font-size:12px;color:#bbd1de}.back-to-top{position:fixed;right:20px;bottom:22px;width:42px;height:42px;border:0;border-radius:50%;background:var(--nav);color:#fff;box-shadow:0 2px 9px #102e4633;cursor:pointer;opacity:0;visibility:hidden;pointer-events:none;transition:opacity .2s}.back-to-top.is-visible{opacity:1;visibility:visible;pointer-events:auto}
@media(max-width:1024px){.shell{width:calc(100% - 44px)}.brand-caption{font-size:12px}.three-col{gap:13px}}
@media(max-width:920px){.shell{width:calc(100% - 44px)}.brand-inner{height:62px;justify-content:space-between;gap:8px}.brand-caption,.desktop-nav{display:none}.brand{margin-inline:auto}.brand-name{display:none}.brand .media-frame img{max-height:30px}.join-link{height:40px;min-height:40px;padding:0 11px;font-size:12px}.menu-toggle{display:flex;flex-direction:column;justify-content:center;align-items:center;gap:5px;width:40px;height:40px;flex:0 0 40px;border:1px solid var(--line);border-radius:8px;background:#fff;cursor:pointer}.menu-toggle span{display:block;width:19px;height:2px;background:var(--ink)}.drawer-overlay{display:block;position:fixed;inset:0;background:rgba(3,22,34,.58);z-index:29;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;z-index:30;width:min(86vw,340px);overflow-y:auto;background:#fff;padding:16px 19px 25px;transform:translateX(-103%);visibility:hidden;pointer-events:none;transition:transform .22s,visibility .22s;box-shadow:6px 0 25px #0002}.mobile-drawer.is-open{transform:translateX(0);visibility:visible;pointer-events:auto}.mobile-drawer .drawer-head{display:flex;align-items:center;justify-content:space-between;margin-bottom:14px}.drawer-close{width:40px;height:40px;border:0;background:var(--pale);color:var(--ink);font-size:28px;cursor:pointer}.drawer-group{font-size:12px;letter-spacing:.1em;color:var(--sub);border-bottom:1px solid var(--line);margin:17px 0 5px}.mobile-drawer>a{display:block;color:var(--ink);padding:11px;border-radius:7px}.mobile-drawer>a[aria-current]{background:var(--mint);border-left:3px solid var(--cyan);font-weight:800}.quick-links{display:flex;justify-content:space-between;gap:12px;flex-wrap:wrap;padding:19px 0 25px;font-size:13px}.quick-links a{color:var(--ink)}.nojs-nav{display:flex}}
@media(max-width:760px){.two-col,.two-col--wide,.three-col,.editor-grid,.feature-strip,.gallery,.service-layout,.footer-grid{grid-template-columns:1fr}.editor-grid{gap:15px}.service-menu{order:2}.service-layout>div:last-child{order:1}.gallery .gallery-card:nth-child(2){margin-top:0}.timeline{grid-template-columns:1fr 1fr}.timeline article:nth-child(3){border-left:0}.related-links{grid-template-columns:1fr}.footer-grid{gap:22px}.media-frame--hero{--media-limit:250px}}
@media(max-width:640px){body{font-size:15px;line-height:1.78}.shell{width:calc(100% - 32px)}h1{font-size:clamp(27px,7.7vw,32px)}h2{font-size:clamp(20px,5.5vw,23px)}h3{font-size:18px}.lead{font-size:16px}.page-intro{padding:28px 0 15px}.panel,.mini-article,.soft-panel{padding:18px}.index-list,.timeline{grid-template-columns:1fr}.timeline article+article{border-left:0}.section-heading{align-items:start;display:block}.section-heading small{display:block;margin-top:4px}.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--logo{--media-limit:30px}.footer-grid nav{grid-template-columns:1fr 1fr}.article-section{margin-block:32px}.brand-inner{gap:5px}.brand{min-width:0}.join-link{font-size:12px;padding:0 9px}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*,*:before,*:after{animation-duration:.01ms!important;transition-duration:.01ms!important}}