:root{color-scheme:dark;--bg:#080A0D;--surface:#0D1015;--surface2:#12161C;--surface3:#171C23;--hover:#1B2129;--text:#C7CDD5;--muted:#9098A3;--title:#F5F7FA;--blue:#5C7CFA;--bright:#6EA8FF;--ice:#8ED8FF;--border:rgba(255,255,255,.09);--strongborder:rgba(255,255,255,.16);font-family:Arial,"PingFang SC","Microsoft YaHei",sans-serif}
*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:86px}body{margin:0;background:var(--bg);color:var(--text);font-size:16px;line-height:1.8}h1,h2,h3{color:var(--title);line-height:1.38}h1{font-size:32px;margin:8px 0 18px}h2{font-size:24px;margin:0 0 17px}h3{font-size:19px;margin:0 0 12px}p{margin:0 0 16px}a{color:var(--bright);text-decoration:none}a:hover{text-decoration:underline}a:focus-visible,button:focus-visible,summary:focus-visible{outline:3px solid var(--ice);outline-offset:3px;border-radius:4px}button{font:inherit;cursor:pointer}strong{color:var(--title)}.container{width:min(1200px,calc(100% - 48px));margin-inline:auto}.reading-width{max-width:800px;margin-inline:auto}.site-header{position:sticky;top:0;z-index:30;background:rgba(8,10,13,.96);border-bottom:1px solid var(--border)}.nav-shell{height:68px;width:min(1200px,calc(100% - 48px));margin:auto;display:flex;align-items:center;gap:20px;min-width:0}.brand{display:flex;align-items:center;min-width:110px;max-width:140px;flex-shrink:0}.brand .media-natural{padding:0;background:transparent}.brand img{max-height:34px}.brand-fallback{display:none;color:#F5F7FA;font-weight:800;font-size:20px;white-space:nowrap}.brand:has(.missing-media) .missing-media{display:none}.brand:has(.missing-media) .brand-fallback{display:block}.desktop-nav{display:flex;flex:1;align-items:center;justify-content:space-between;gap:12px;white-space:nowrap;min-width:0}.desktop-nav a{font-size:14px;color:var(--text)}.desktop-nav a[aria-current],.desktop-nav a:hover{color:var(--bright)}.menu-trigger{background:var(--surface2);border:1px solid var(--strongborder);border-radius:9px;color:var(--title);padding:9px 13px;white-space:nowrap}.enter-button,.primary-link{display:inline-flex;align-items:center;justify-content:center;white-space:nowrap;background:var(--blue);color:white;padding:9px 16px;border-radius:9px;font-weight:700;font-size:14px}.enter-button:hover,.primary-link:hover{background:#6EA8FF;color:#080A0D;text-decoration:none}.skip-link{position:absolute;top:-70px;left:8px;z-index:100;background:var(--surface3);padding:8px}.skip-link:focus{top:8px}.menu-backdrop{position:fixed;inset:68px 0 0;background:rgba(0,0,0,.48);z-index:31}.menu-panel{position:absolute;right:max(24px,calc((100% - 1200px)/2));top:68px;width:min(780px,calc(100vw - 48px));max-height:min(76vh,740px);overflow-y:auto;background:var(--surface2);border:1px solid var(--strongborder);border-radius:0 0 14px 14px;padding:20px;box-shadow:0 16px 40px rgba(0,0,0,.5);z-index:32}.menu-panel[hidden],.menu-backdrop[hidden]{display:none!important}.menu-head{display:flex;align-items:center;justify-content:space-between;margin-bottom:16px}.close-button{background:var(--surface3);color:var(--title);border:1px solid var(--strongborder);border-radius:8px;padding:5px 12px}.menu-groups{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:20px}.menu-groups h2{font-size:16px;margin-bottom:7px}.menu-groups ul{list-style:none;padding:0;margin:0}.menu-groups a{display:block;padding:4px 0;color:var(--text);font-size:14px}.menu-map{display:block;border-top:1px solid var(--border);margin-top:16px;padding-top:12px;font-weight:bold}.site-main{padding-bottom:64px;min-height:60vh}.article-top{padding-top:22px}.breadcrumbs{display:flex;gap:12px;align-items:center;flex-wrap:wrap;font-size:13px;color:var(--muted)}.breadcrumbs a{color:var(--muted)}.page-heading{max-width:850px;margin:28px 0 22px}.eyebrow{letter-spacing:.12em;color:var(--bright);font-size:13px;font-weight:bold;margin:0 0 8px}.dek{font-size:17px;color:var(--text);max-width:820px}.local-nav{display:flex;gap:8px;align-items:center;flex-wrap:wrap;margin-bottom:33px;border-block:1px solid var(--border);padding:12px 0}.local-nav>span{font-size:13px;color:var(--muted);margin-right:4px}.local-nav a{font-size:13px;color:var(--text);background:var(--surface2);border:1px solid var(--border);border-radius:16px;padding:3px 11px}.local-nav a[aria-current]{border-color:var(--blue);color:var(--bright)}.section{margin:38px auto}.panel,.note,.reading-card,.feature-box{background:var(--surface);border:1px solid var(--border);border-radius:14px;padding:22px}.panel--muted{background:var(--surface2)}.lede{font-size:19px;color:var(--title);line-height:1.7}.muted,.fine,.caption,.footnote{color:var(--muted);font-size:13px}.two-col{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:20px}.three-col{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:20px}.split{display:grid;grid-template-columns:minmax(0,1.5fr) minmax(0,1fr);gap:28px}.split>*{min-width:0}.list-plain{list-style:none;padding:0;margin:0}.list-plain li{padding:14px 0;border-bottom:1px solid var(--border)}.list-plain li:last-child{border-bottom:0}.numbered{counter-reset:points}.numbered>li{counter-increment:points;position:relative;padding-left:42px}.numbered>li:before{content:counter(points,decimal-leading-zero);position:absolute;left:0;top:15px;font-size:13px;color:var(--bright)}.body-copy{max-width:800px;margin:auto}.body-copy p{line-height:1.85}.pullquote{border-left:3px solid var(--blue);padding:18px 24px;background:var(--surface2);color:var(--title);margin:24px 0}.callout{border-left:3px solid var(--bright);padding:13px 19px;background:var(--surface2);margin:20px 0}.data-table{width:100%;border-collapse:collapse;font-size:14px}.data-table th,.data-table td{padding:12px;text-align:left;vertical-align:top;border-bottom:1px solid var(--border)}.data-table th{color:var(--title);background:var(--surface2);font-weight:700}.table-scroll{overflow-x:auto;border:1px solid var(--border);border-radius:12px}.table-scroll .data-table{min-width:580px}.step{border-left:2px solid var(--blue);padding:4px 0 20px 23px;margin-left:10px;position:relative}.step:before{content:"";position:absolute;left:-7px;top:9px;background:var(--blue);border-radius:100%;width:12px;height:12px}.step:last-child{padding-bottom:0}.media-natural,.media-frame{display:grid;place-items:center;min-width:0;padding:8px;border-radius:12px;background:#0D1015}.media-natural>img{display:block;width:auto;height:auto;max-width:100%;max-height:var(--image-max-height,280px);object-fit:contain;object-position:center}.media-frame{width:100%;aspect-ratio:var(--media-ratio,16 / 9)}.media-frame>img{display:block;width:100%;height:100%;object-fit:contain;object-position:center}.missing-media{display:flex;align-items:center;justify-content:center;min-height:110px;border:1px dashed var(--strongborder);background:var(--surface);color:var(--muted);font-size:13px;border-radius:12px}.poster .media-natural>img{max-height:240px}.media-caption{margin-top:10px;font-size:13px;color:var(--muted);line-height:1.7}.motion-note{font-size:12px;color:var(--muted);margin:7px 0}.image-entry{background:var(--surface);border:1px solid var(--border);padding:12px;border-radius:12px;min-width:0}.image-entry h3{margin:10px 0 5px;font-size:16px}.image-entry p{margin:0;font-size:13px;color:var(--muted)}.related{margin:45px auto 0;border-top:1px solid var(--strongborder);padding-top:28px}.related-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:12px}.related-grid a{display:flex;flex-direction:column;gap:6px;background:var(--surface2);border:1px solid var(--border);border-radius:12px;padding:18px}.related-grid span{font-size:13px;color:var(--muted)}.related-grid strong{font-size:15px}.home-hero{padding:46px 0 10px;display:grid;grid-template-columns:minmax(0,2fr) minmax(210px,.8fr);gap:34px;align-items:end}.home-hero h1{font-size:37px}.hero-questions{border-left:2px solid var(--blue);padding-left:20px}.hero-questions p{margin:9px 0;color:var(--title)}.question{display:block;border-top:1px solid var(--strongborder);padding:22px 4px}.question h3{margin:0 0 8px}.question p{color:var(--text)}.question a{font-size:14px}.editor-pick{background:var(--surface2);border:1px solid var(--border);padding:24px;border-radius:14px}.index-line{display:flex;align-items:baseline;gap:14px;border-bottom:1px solid var(--border);padding:14px 0}.index-line .digit{font-size:13px;color:var(--bright);min-width:24px}.index-line div{flex:1}.index-line p{font-size:14px;margin:0}.tag{display:inline-block;border:1px solid var(--strongborder);border-radius:30px;padding:2px 12px;color:var(--muted);font-size:12px}.term-index{display:flex;flex-wrap:wrap;gap:9px;margin:16px 0 28px}.term-index a{border:1px solid var(--border);border-radius:18px;padding:4px 11px;background:var(--surface2)}.term-row{padding:20px 0;border-bottom:1px solid var(--strongborder)}.term-row h2{font-size:20px}.term-row dl{display:grid;grid-template-columns:100px 1fr;gap:8px;margin:0}.term-row dt{color:var(--bright);font-weight:bold}.term-row dd{margin:0}.flow-note{font-size:14px;color:var(--muted)}.rule-banner{padding:18px 22px;background:var(--surface2);border-left:3px solid var(--blue)}.story{max-width:760px;margin:auto}.story>p:first-of-type:first-letter{font-size:44px;color:var(--bright);float:left;line-height:1;margin:7px 10px 0 0}.story h2{margin-top:34px}.file-label{color:var(--muted);font-size:12px;letter-spacing:.08em}.faq-item{padding:17px 0;border-bottom:1px solid var(--border)}.faq-item h2{font-size:18px;margin-bottom:7px}.faq-item p{margin:0}.site-footer{background:#050608;border-top:1px solid var(--border);padding:35px 0}.footer-grid{display:grid;grid-template-columns:1.3fr 1fr;gap:40px}.footer-grid h2{font-size:16px}.footer-brand{font-size:22px;color:var(--title);font-weight:bold}.footer-grid p{font-size:13px;margin:5px 0}.back-to-top{position:fixed;right:24px;bottom:22px;background:var(--blue);border:0;color:white;border-radius:50%;width:43px;height:43px;z-index:20}.back-to-top[hidden]{display:none}
@media(max-width:1050px){.desktop-nav{display:none}.nav-shell{justify-content:space-between}.brand{margin-right:auto}.menu-panel{right:20px}.menu-groups{grid-template-columns:repeat(2,minmax(0,1fr))}}
@media(max-width:700px){body{font-size:15px}.container,.nav-shell{width:calc(100% - 32px)}h1{font-size:27px}h2{font-size:21px}h3{font-size:18px}.nav-shell{height:65px;gap:9px}.brand{max-width:96px;min-width:0}.brand img{max-width:96px}.brand-fallback{font-size:17px}.menu-trigger{min-height:44px;padding:8px 11px;font-size:14px}.enter-button{padding:9px 11px;min-height:44px;font-size:13px}.menu-backdrop{inset:0;background:rgba(0,0,0,.65)}.menu-panel{position:fixed;top:auto;bottom:0;left:0;right:0;width:100%;max-height:85vh;max-height:85dvh;border-radius:18px 18px 0 0;padding:18px 16px calc(18px + env(safe-area-inset-bottom,0px));overflow-y:auto}.menu-groups{grid-template-columns:1fr;gap:18px}.menu-groups ul{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:2px 12px}.menu-groups a{padding:8px 0}.page-heading{margin-top:20px}.dek{font-size:15px}.article-top{padding-top:15px}.local-nav{margin-bottom:24px}.home-hero{display:block;padding-top:30px}.home-hero h1{font-size:29px}.hero-questions{margin-top:23px}.section{margin:28px auto}.two-col,.three-col,.split,.related-grid,.footer-grid{grid-template-columns:minmax(0,1fr)}.panel,.note,.reading-card,.feature-box{padding:17px}.poster .media-natural>img{max-height:160px}.media-natural>img{max-height:min(var(--image-max-height,210px),210px)}.table-scroll .data-table{font-size:13px}.term-row dl{grid-template-columns:1fr;gap:2px}.term-row dd{margin-bottom:10px}.image-entry .media-frame{max-height:165px}.image-entry .media-natural>img{max-height:155px}.back-to-top{right:14px;bottom:14px}}
@media(max-width:360px){.brand{max-width:88px}.enter-button{padding:8px 9px}.nav-shell{gap:6px}.menu-trigger{padding:8px}.brand img{max-width:88px}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}.animated-media img{visibility:hidden}.animated-media:after{content:"动态图像已按减少动态效果的系统偏好隐藏";display:block;padding:10px;color:var(--muted);font-size:13px}}