:root{--base:#F6FAFC;--surface:#fff;--soft:#EAF6FA;--soft2:#EDF4F8;--cyan:#25C8D1;--sky:#25B6E8;--blue:#1787DB;--ocean:#174B78;--heading:#183A56;--text:#31485D;--muted:#687D8E;--line:#DCE9F0;--footer:#123653;--max:1180px}*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:30px}body{margin:0;background:var(--base);color:var(--text);font:16px/1.8 Arial,'PingFang SC','Microsoft YaHei',sans-serif;overflow-wrap:break-word}body.drawer-open{overflow:hidden}a{color:var(--ocean);text-underline-offset:3px}a:hover{color:var(--blue)}button{font:inherit;cursor:pointer}button,a,summary{outline-offset:3px}a:focus-visible,button:focus-visible,summary:focus-visible{outline:3px solid var(--cyan)}h1,h2,h3,h4{color:var(--heading);line-height:1.4;margin:0 0 .7em}h1{font-size:clamp(32px,3.4vw,42px);letter-spacing:-.035em}h2{font-size:clamp(23px,2.2vw,27px)}h3{font-size:19px}p{margin:0 0 1.1em}ul,ol{padding-left:1.4em}li+li{margin-top:.35em}img{max-width:100%}.wrap{max-width:var(--max);padding:0 28px;margin:auto}.skip-link{position:absolute;top:-100px;left:15px;z-index:100;padding:10px;background:#fff}.skip-link:focus{top:10px}.site-header{background:#fff;position:relative;z-index:30;border-bottom:1px solid var(--line)}.toolbar{height:72px;display:flex;align-items:center;gap:20px}.brand{display:flex;align-items:center;min-width:120px;text-decoration:none}.brand img{display:block;max-height:38px;width:auto;height:auto;object-fit:contain}.brand-fallback{font-size:23px;font-weight:800;color:var(--ocean);line-height:1.05}.brand-fallback span{display:block;font-size:10px;letter-spacing:.12em;margin-top:4px}.header-note{flex:1;text-align:center;color:var(--muted);font-size:14px;letter-spacing:.13em}.entry-button,.button{display:inline-flex;align-items:center;justify-content:center;gap:12px;background:var(--ocean);color:#fff;padding:10px 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p{color:var(--muted)}.card-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:18px}.topic-grid{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:14px}.topic-card,.info-card{background:#fff;border:1px solid var(--line);border-radius:12px;padding:22px;min-width:0}.topic-card{text-decoration:none;display:block;transition:border-color .2s,transform .2s}.topic-card:hover{border-color:var(--cyan);transform:translateY(-2px)}.topic-card strong{display:block;font-size:18px;color:var(--heading);margin-bottom:10px}.topic-card p{font-size:14px;color:var(--muted);margin:0;line-height:1.7}.topic-card .arrow{display:block;text-align:right;color:var(--blue);margin-top:8px}.editorial-grid{display:grid;grid-template-columns:1.8fr 1fr;gap:20px}.editorial-main{background:var(--ocean);color:#e9f8ff;border-radius:14px;padding:32px}.editorial-main h3{color:#fff;font-size:25px}.editorial-main a{color:#fff}.editorial-side{display:grid;gap:16px}.editorial-side article{padding:23px;background:#fff;border:1px solid var(--line);border-radius:12px}.editorial-side h3{margin-top:0}.editorial-side a,.text-link{font-weight:700}.feature-row{display:grid;grid-template-columns:1fr 1fr;gap:36px;align-items:center}.feature-row.reverse .feature-media{order:-1}.feature-row p{max-width:650px}.text-link{text-decoration-thickness:1px}.rule-notes{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:14px}.rule-notes article{background:#fff;border-top:4px solid var(--cyan);border-radius:10px;padding:24px}.steps{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:14px;counter-reset:step}.steps article{padding:22px;background:#fff;border:1px solid var(--line);border-radius:12px}.steps article::before{counter-increment:step;content:'0' counter(step);display:block;color:var(--blue);font-weight:900;font-size:22px;margin-bottom:12px}.steps h3{font-size:18px}.page-intro{padding:40px 0 22px}.page-intro 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@media(max-width:1180px){.wrap{padding-inline:22px}.topic-grid{grid-template-columns:repeat(3,minmax(0,1fr))}}
@media(max-width:980px){.toolbar{height:63px;justify-content:space-between;gap:10px}.menu-toggle{display:flex}.brand{min-width:0;justify-content:center;flex:1}.brand img{max-height:30px}.header-note,.desktop-nav{display:none}.entry-button{min-height:40px;padding:7px 12px;font-size:13px}.hero-grid{gap:24px}.quick-list{justify-content:flex-start}.article-aside{grid-template-columns:minmax(0,1fr) 220px;gap:24px}.footer-bottom{display:block}.footer-bottom p+p{margin-top:9px}}
@media(max-width:760px){.hero-grid,.feature-row,.editorial-grid,.two-col,.article-aside,.footer-grid{grid-template-columns:1fr}.hero-grid{padding-top:35px;padding-bottom:35px}.hero-media{order:-1}.feature-row.reverse .feature-media{order:0}.editorial-side{grid-template-columns:repeat(2,minmax(0,1fr))}.topic-grid,.card-grid,.three-col,.rule-notes,.related-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.steps{grid-template-columns:repeat(2,minmax(0,1fr))}.aside-box{position:static}.section{padding:39px 0}.footer-grid{gap:24px}}
@media(max-width:640px){body{font-size:15px}.wrap{padding-inline:16px}.hero h1{font-size:29px}.page-intro h1{font-size:27px}.hero p,.page-intro p{font-size:15px}.hero-grid{gap:22px}.media--hero{height:200px}.media--feature{height:180px}.media--card{height:145px}.media--banner{height:150px}.media--mobile{height:290px;max-width:250px}.topic-grid,.card-grid,.three-col,.rule-notes,.exhibition,.related-grid,.editorial-side{grid-template-columns:1fr}.steps{grid-template-columns:repeat(2,minmax(0,1fr))}.section{padding:31px 0}.section-heading{margin-bottom:17px}.topic-card,.info-card{padding:17px}.content-panel{padding:19px}.editorial-main{padding:23px}.hero-actions{gap:10px}.button{padding:9px 13px;font-size:14px}.quick-group{flex-wrap:wrap}.footer-links{grid-template-columns:repeat(2,minmax(0,1fr))}.site-footer{padding-bottom:90px}.bottom-nav{position:fixed;display:grid;grid-template-columns:repeat(4,1fr);bottom:0;left:0;right:0;z-index:28;background:#fff;border-top:1px solid var(--line);padding-bottom:env(safe-area-inset-bottom,0px);box-shadow:0 -2px 14px #10305010}.bottom-nav a{min-height:52px;display:grid;place-items:center;font-size:13px;font-weight:700;text-decoration:none;color:var(--ocean)}.bottom-nav a[aria-current]{background:var(--soft);color:var(--blue)}.back-top{bottom:78px;right:12px;width:38px;height:38px}.header-note{display:none}}
@media(max-height:470px) and (max-width:640px){.bottom-nav{position:static}.site-footer{padding-bottom:26px}.back-top{bottom:14px}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*,*::before,*::after{transition-duration:.01ms!important;animation-duration:.01ms!important}}
@media(max-width:980px){noscript .mobile-drawer{position:static;transform:none;visibility:visible;pointer-events:auto;width:100%;box-shadow:none;padding:14px 22px}noscript .drawer-head button{display:none}}