:root{--bg:#F4F7FA;--paper:#fff;--mist:#EAF1F6;--aqua:#E9F8F8;--nav:#102E46;--nav2:#163C57;--teal:#13B8C5;--blue:#237BD3;--heading:#18364B;--text:#344C60;--muted:#64798A;--line:#DCE6ED}*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;background:var(--bg);color:var(--text);font:16px/1.8 Arial,"PingFang SC","Microsoft YaHei",sans-serif;overflow-wrap:break-word}a{color:#1764A7;text-underline-offset:3px}a:hover{color:#094871}button{font:inherit;cursor:pointer}img{max-width:100%;height:auto}h1,h2,h3{color:var(--heading);line-height:1.38;letter-spacing:-.018em;margin:0 0 .75em}h1{font-size:36px}h2{font-size:27px}h3{font-size:20px}p{margin:0 0 1.12em}ul,ol{padding-left:1.4em}li{margin:.45em 0}section{scroll-margin-top:24px}section+section{margin-top:58px}.shell{max-width:1200px;padding:0 28px;margin:0 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var(--line);padding-bottom:24px;margin-bottom:38px}.page-intro p{margin-bottom:0}.hero{display:grid;grid-template-columns:52fr 48fr;gap:28px;align-items:center;padding:21px 0 30px}.hero h1{font-size:42px}.hero p{max-width:590px}.hero-actions{display:flex;flex-wrap:wrap;gap:12px;margin-top:24px}.action-link{display:inline-block;padding:10px 20px;border-radius:10px;text-decoration:none;font-weight:700;background:var(--nav);color:white}.action-link:hover{background:var(--nav2);color:white}.action-link.secondary{background:#e5f6f7;color:#075769}.media-frame{margin:0;display:flex;align-items:center;justify-content:center;min-width:0;width:100%;padding:8px;border-radius:14px;background:var(--mist);border:1px solid var(--line)}.media-frame 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b{font-size:14px;color:#1597a4}.directory-item h3{margin:0 0 4px}.directory-item p{font-size:14px;margin:0 0 7px}.directory-item a{font-size:14px;font-weight:700}.editorial-grid{display:grid;grid-template-columns:2fr 1fr;gap:22px}.feature-story{padding:31px;background:#fff;border-left:4px solid var(--teal)}.mini-stories{display:grid;gap:14px}.mini-story{padding:21px;background:var(--mist);border-radius:11px}.split{display:grid;grid-template-columns:1fr 1.1fr;gap:36px;align-items:center}.split.reverse{grid-template-columns:1.1fr 1fr}.split>.media-frame,.split>div{min-width:0}.text-band{background:#fff;border-block:1px solid var(--line);padding:28px 0}.text-columns{display:grid;grid-template-columns:repeat(3,1fr);gap:26px}.text-columns>div+div{border-left:1px solid var(--line);padding-left:26px}.lesson-stack{display:grid;grid-template-columns:repeat(3,1fr);gap:18px}.lesson{padding:24px;border:1px solid var(--line);background:#fff;border-radius:12px}.lesson:nth-child(2){transform:translateY(15px);background:var(--aqua)}.lesson:nth-child(3){transform:translateY(29px)}.route-flow{display:grid;grid-template-columns:repeat(4,1fr);gap:14px}.route-step{padding:18px;border-top:3px solid #3b8ea2;background:#fff}.route-step strong{display:block}.route-step b{color:#168b9a;font-size:13px}.notice{padding:23px 27px;background:var(--aqua);border-left:3px solid var(--teal);border-radius:4px 11px 11px 4px}.article-layout{display:grid;grid-template-columns:minmax(0,1fr) 245px;gap:44px;align-items:start}.article-copy{max-width:790px;min-width:0}.article-copy>section+section{border-top:1px solid var(--line);padding-top:32px;margin-top:36px}.fact-aside{background:#fff;border:1px solid var(--line);padding:21px;border-radius:12px;font-size:14px}.fact-aside h2{font-size:18px}.fact-aside a{display:block;padding:8px 0}.section-nav{display:flex;flex-wrap:wrap;gap:10px;margin:10px 0 35px}.section-nav 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56px;margin:0;border-left:2px solid var(--line)}.numbered li:before{content:counter(steps,decimal-leading-zero);position:absolute;left:13px;top:17px;color:#128995;font-weight:800}.numbered li+li{border-top:1px solid var(--line)}.matrix{display:grid;grid-template-columns:repeat(3,1fr);gap:16px}.matrix-item{padding:22px;background:#fff;border-radius:9px;border-top:4px solid var(--blue)}.matrix-item:nth-child(2){border-color:var(--teal)}.matrix-item:nth-child(3){border-color:#6982ab}.two-up{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:26px}.article-panel{padding:25px;background:white;border:1px solid var(--line);border-radius:10px}.gallery{display:grid;grid-template-columns:1.08fr .92fr;gap:25px;align-items:start}.gallery>*{min-width:0}.gallery>div:nth-child(2){padding-top:45px}.gallery-entry{margin-bottom:35px}.gallery-entry h3{margin-top:12px}.manual{max-width:850px}.manual>section{padding:22px 0;border-top:1px solid var(--line)}.rule-index{max-width:680px;padding:20px;background:#fff;border:1px solid var(--line);border-radius:12px}.rule-index a{display:block;padding:8px 12px;border-bottom:1px solid var(--line)}.rule-index a:last-child{border:0}.faq details{background:#fff;border:1px solid var(--line);border-radius:9px;margin-bottom:10px;padding:13px 18px}.faq summary{cursor:pointer;color:var(--heading);font-weight:700}.faq details p{margin:10px 0 2px}.help-layout{display:grid;grid-template-columns:240px minmax(0,1fr);gap:36px;align-items:start}.help-aside{background:var(--mist);padding:20px;border-radius:12px;position:sticky;top:20px}.help-aside a{display:block;padding:7px 0}.help-main section+section{padding-top:25px;border-top:1px solid var(--line);margin-top:30px}.related-links{margin-top:55px;padding-top:26px;border-top:2px solid var(--nav)}.related-links h2{font-size:23px}.related-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:12px}.related-grid a{background:#fff;padding:17px;border:1px solid var(--line);text-decoration:none;font-weight:700;border-radius:9px}.site-footer{background:#0B2539;color:#DCECF5;padding:46px 0 18px}.site-footer strong{color:#fff;font-size:20px}.site-footer strong small{font-size:11px;letter-spacing:.12em}.footer-grid{display:grid;grid-template-columns:1.2fr 1fr;gap:45px}.footer-grid p{max-width:600px;font-size:14px}.footer-grid nav{display:grid;grid-template-columns:repeat(2,1fr);gap:8px}.footer-grid a{color:#dcecf5;font-size:14px}.footer-bottom{margin-top:28px;padding-top:15px;border-top:1px solid #31536a;font-size:12px;color:#b0c9d7}.back-to-top{position:fixed;bottom:18px;right:18px;background:var(--nav);color:white;border:0;border-radius:50%;width:42px;height:42px;z-index:8}.back-to-top[hidden]{display:none}:focus-visible{outline:3px solid #00a2ba;outline-offset:3px}
@media(max-width:1100px){.shell{padding-inline:22px}.article-layout{gap:25px}.brand-caption{font-size:12px}}
@media(max-width:920px){.brand-strip{height:62px;justify-content:space-between;gap:10px}.brand-caption,.desktop-nav{display:none}.brand{margin:auto}.brand-fallback{font-size:21px}.brand-fallback small{font-size:8px}.media-frame--logo img{max-height:30px}.register-link{margin:0;padding:7px 12px;font-size:13px;height:38px;display:grid;place-items:center}.menu-toggle{width:40px;height:40px;border:0;background:transparent;display:flex;flex-direction:column;justify-content:center;align-items:center;gap:5px;padding:0;flex:0 0 40px}.menu-toggle span{width:21px;height:2px;background:var(--nav)}.drawer-shade{display:block;position:fixed;inset:0;background:rgba(8,24,37,.55);opacity:0;visibility:hidden;pointer-events:none;z-index:29;transition:opacity .2s,visibility .2s}.mobile-drawer{display:block;position:fixed;inset:0 auto 0 0;width:min(86vw,340px);overflow-y:auto;transform:translateX(-101%);transition:transform .2s;background:#fff;z-index:30;padding:20px;visibility:hidden}.drawer-open{overflow:hidden}.drawer-open .drawer-shade{opacity:1;visibility:visible;pointer-events:auto}.drawer-open .mobile-drawer{transform:translateX(0);visibility:visible}.drawer-top{display:flex;align-items:center;justify-content:space-between;border-bottom:1px solid var(--line);padding-bottom:12px}.drawer-top button{height:42px;width:42px;border:0;background:var(--mist);border-radius:8px;font-size:29px}.drawer-group{padding:18px 0;border-bottom:1px solid var(--line)}.drawer-label{display:block;color:var(--muted);font-size:12px;font-weight:800;margin-bottom:7px}.drawer-group a{display:block;padding:10px 12px;border-radius:6px;text-decoration:none;color:var(--heading);font-weight:700}.drawer-group a.is-current{background:var(--mist);border-left:3px solid var(--teal)}.no-js-nav{display:flex;flex-wrap:wrap;gap:10px;background:#f2f7fa;padding:12px 22px}.no-js-nav a{font-size:13px}.mobile-quick{display:flex;justify-content:space-between;gap:8px;padding-block:14px 22px;font-size:13px}.mobile-quick a{white-space:nowrap}.hero h1{font-size:37px}}
@media(max-width:760px){.hero,.split,.split.reverse,.editorial-grid,.article-layout,.help-layout,.gallery{grid-template-columns:1fr}.hero{gap:20px}.hero .media-frame{grid-row:2}.article-layout aside{order:2}.help-main{order:1}.help-aside{position:static;order:2}.lesson-stack,.matrix,.text-columns{grid-template-columns:1fr}.text-columns>div+div{padding:0;border:0;border-top:1px solid var(--line);padding-top:16px}.lesson:nth-child(n){transform:none}.route-flow,.process{grid-template-columns:repeat(2,1fr)}.gallery>div:nth-child(2){padding:0}.gallery-entry{margin-bottom:26px}.related-grid{grid-template-columns:1fr}.footer-grid{grid-template-columns:1fr;gap:20px}.page-intro{margin-bottom:25px}.split .media-frame{max-width:560px}.section-heading{margin-bottom:18px}}
@media(max-width:640px){body{font-size:15px;line-height:1.78}.shell{padding-inline:16px}main>.shell:first-child{padding-top:20px}main{padding-bottom:30px}h1{font-size:27px}h2{font-size:22px}h3{font-size:18px}.hero h1{font-size:30px}.lead{font-size:16px}.hero{padding:10px 0 15px}.directory,.two-up{grid-template-columns:1fr}.directory-item{padding:15px 0}.section-nav{gap:7px}.section-nav a{font-size:13px;padding:7px 10px}.feature-story{padding:22px}.mini-story,.lesson,.article-panel{padding:19px}.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}.media-frame--hero.media-placeholder{min-height:105px}.section+section,section+section{margin-top:35px}.route-flow,.process{gap:8px}.process-step,.route-step{padding:13px}.mobile-quick{font-size:12px}.site-footer{padding-top:33px}.footer-grid nav{gap:4px}}
@media(max-width:380px){.brand-fallback{font-size:18px}.register-link{padding:6px 8px;font-size:12px}.mobile-quick{flex-wrap:wrap;justify-content:center;column-gap:17px}.directory-item{grid-template-columns:30px 1fr}}
@media(prefers-reduced-motion:reduce){*,*:before,*:after{scroll-behavior:auto!important;animation-duration:.01ms!important;transition-duration:.01ms!important}}