:root{--bg:#F4F7FA;--white:#fff;--pale:#EAF1F6;--mint:#E9F8F8;--nav:#102E46;--dark:#163C57;--aqua:#13B8C5;--blue:#237BD3;--heading:#18364B;--text:#344C60;--muted:#64798A;--line:#DCE6ED;--footer:#0B2539;--max:1200px}*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:24px}body{margin:0;background:var(--bg);font-family:Arial,'PingFang SC','Microsoft YaHei',sans-serif;color:var(--text);font-size:16px;line-height:1.8;overflow-wrap:break-word}button{font:inherit}a{color:#1764a2;text-underline-offset:4px}a:hover{color:#0b748a}a:focus-visible,button:focus-visible,summary:focus-visible{outline:3px solid #00a9b8;outline-offset:3px}img{max-width:100%}.wrap{width:min(calc(100% - 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21px;color:var(--heading)}.hero p{margin:0 0 15px}.hero .hero-intro{font-size:17px}.action-row{display:flex;flex-wrap:wrap;gap:12px;margin-top:24px}.button-link{display:inline-flex;align-items:center;min-height:43px;padding:9px 18px;border-radius:9px;background:var(--nav);color:#fff;text-decoration:none;font-weight:700;font-size:14px}.button-link.secondary{background:transparent;color:var(--nav);border:1px solid #9ab2c3}.button-link:hover{background:#17687a;color:#fff}.topic-directory{padding:29px 35px;background:#fff;border-top:3px solid var(--aqua)}.topic-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:0 38px}.topic-item{padding:19px 0;border-bottom:1px solid var(--line);min-width:0}.topic-item h3{font-size:19px;margin:0 0 5px}.topic-item p{font-size:15px;margin:0 0 7px}.topic-item a{font-weight:700}.feature-grid{display:grid;grid-template-columns:2fr 1fr;gap:24px;align-items:start}.feature-main{padding:28px;background:var(--mint);border-left:4px solid 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var(--line)}.info-table thead th{background:var(--nav);color:#fff;border-top:0}.info-table tbody tr:nth-child(even){background:#f4f7fa}.taxonomy{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:16px}.taxonomy article{background:#fff;padding:20px;border-top:4px solid var(--aqua)}.taxonomy h3{margin:0 0 8px}.gallery-grid{display:grid;grid-template-columns:1fr 1fr;gap:27px}.gallery-item{background:#fff;padding:20px;min-width:0}.gallery-item:nth-child(2){margin-top:42px}.gallery-item h3{margin-top:13px}.rule-directory{max-width:760px;background:#fff;padding:25px;border:1px solid var(--line)}.rule-directory ol{margin:0;padding-left:24px}.rule-directory li{margin:10px 0}.faq-item{border-bottom:1px solid var(--line);background:#fff;margin-bottom:6px}.faq-item summary{cursor:pointer;color:var(--heading);font-weight:700;padding:15px 18px}.faq-item[open] summary{background:var(--mint)}.faq-item p{padding:4px 18px 17px;margin:0}.about-layout{display:grid;grid-template-columns:245px minmax(0,1fr);gap:42px;align-items:start}.about-side{background:white;padding:22px;border-top:4px solid var(--aqua)}.about-side a{display:block;padding:8px 0}.about-main{min-width:0}.about-main .section:first-child{margin-top:0}.related{padding:26px 30px;background:#fff;border-top:3px solid var(--nav);margin:46px 0 63px}.related h2{font-size:22px}.related ul{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:20px;list-style:none;padding:0;margin:0}.related a{font-weight:700;text-decoration:none}.site-footer{background:var(--footer);color:#dcecf5;margin-top:44px;padding:40px 0 17px}.footer-grid{display:grid;grid-template-columns:2fr 1fr 1fr;gap:45px}.footer-grid strong{display:block;margin-bottom:12px;color:#fff}.footer-grid a:not(.footer-logo){display:block;color:#dcecf5;text-decoration:none;margin-bottom:7px;font-size:14px}.footer-grid p{margin:8px 0;font-size:14px}.footer-grid .fine-print{max-width:570px;color:#c4d7e1}.footer-logo 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@media(max-width:640px){.wrap{width:calc(100% - 32px)}body{font-size:15px;line-height:1.77}.section{margin-block:36px}.section h2{font-size:22px}.section h3{font-size:18px}.page-intro{padding:15px 0 20px}.page-intro h1{font-size:27px}.intro-lead{font-size:15px}.hero{padding-top:22px}.hero h1{font-size:30px}.hero .hero-intro{font-size:15px}.topic-directory{padding:19px}.topic-grid,.taxonomy,.note-columns,.step-track,.footer-grid,.related ul{grid-template-columns:1fr}.topic-item{padding:13px 0}.feature-main{padding:21px}.note-columns article{padding:19px}.strip{padding:21px}.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}.section h2{margin-bottom:14px}.related{padding:21px;margin-block:34px}.footer-grid>div:last-child{grid-column:auto}.footer-bottom{gap:10px;flex-direction:column}.anchor-nav a{padding:7px 10px;font-size:13px}.page-band{padding:19px}}
@media(prefers-reduced-motion:reduce){*,*::before,*::after{scroll-behavior:auto!important;animation-duration:.01ms!important;transition-duration:.01ms!important}}