:root{--bg:#F4F7FA;--white:#FFFFFF;--soft:#EAF1F6;--mint:#E9F8F8;--nav:#102E46;--dark:#163C57;--teal:#13B8C5;--blue:#237BD3;--title:#18364B;--copy:#344C60;--muted:#64798A;--line:#DCE6ED;--footer:#0B2539;color-scheme:light}*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:25px}body{margin:0;background:var(--bg);font:16px/1.8 Arial,'PingFang SC','Microsoft YaHei',sans-serif;color:var(--copy);overflow-wrap:break-word}a{color:#17649b;text-underline-offset:3px}a:hover{color:#095d67}a:focus-visible,button:focus-visible,summary:focus-visible{outline:3px solid var(--teal);outline-offset:4px}h1,h2,h3{color:var(--title);line-height:1.35;margin:0 0 .7em}h1{font-size:35px;letter-spacing:-.025em}h2{font-size:26px}h3{font-size:20px}p{margin:0 0 1.1em}ul,ol{padding-left:1.4em}li+li{margin-top:.45em}figure{margin:0}img{display:block;max-width:100%}.container{width:min(100% - 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var(--teal)}.stacked-notes{display:grid;gap:18px}.note{padding:22px 24px;background:var(--soft);border-radius:12px}.split{display:grid;grid-template-columns:1fr 1fr;gap:34px;align-items:center}.split.reverse{grid-template-columns:1.2fr .8fr}.surface{background:white;border:1px solid var(--line);border-radius:12px;padding:26px}.soft-surface{background:var(--mint);padding:30px;border-radius:13px}.rule-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:17px}.rule-grid .note:nth-child(2){margin-top:20px}.rule-grid .note:nth-child(3){margin-top:40px}.path-grid{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:14px;counter-reset:route}.path-grid a{display:block;text-decoration:none;border-top:3px solid var(--teal);padding:18px;background:white;color:var(--copy)}.path-grid a:before{counter-increment:route;content:'0' counter(route);display:block;color:var(--blue);font-weight:900}.path-grid 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@media(max-width:1100px){.container{width:min(100% - 44px,1200px)}.brand-note{font-size:12px}.nav-grid a{font-size:13px}}
@media(max-width:920px){.brandbar{width:calc(100% - 32px);height:62px;display:grid;grid-template-columns:40px minmax(0,1fr) auto;gap:10px}.brand{justify-self:center;max-width:100%}.brand .media-frame img{max-height:30px}.brand-fallback{font-size:clamp(12px,3vw,19px)}.brand-note,.desktop-nav{display:none}.entry-link{margin-left:0;min-height:38px;padding:4px 11px;font-size:13px}.menu-toggle{display:flex;flex-direction:column;gap:4px;justify-content:center;align-items:center;width:40px;height:40px;border:1px solid var(--line);border-radius:9px;background:white;cursor:pointer}.menu-toggle span{height:2px;width:18px;background:var(--nav)}.drawer-overlay{display:block;position:fixed;inset:0;z-index:29;background:rgba(6,25,42,.6);opacity:0;visibility:hidden;pointer-events:none;transition:opacity .18s,visibility .18s}.drawer-overlay.is-visible{visibility:visible;opacity:1;pointer-events:auto}.mobile-drawer{display:flex;flex-direction:column;position:fixed;z-index:30;top:0;left:0;bottom:0;width:min(86vw,340px);overflow-y:auto;background:white;padding:20px 22px 35px;transform:translateX(-105%);visibility:hidden;transition:transform .2s,visibility .2s}.mobile-drawer.is-open{transform:translateX(0);visibility:visible}.mobile-drawer .drawer-head{display:flex;justify-content:space-between;align-items:center}.drawer-close{width:40px;height:40px;border:0;background:var(--soft);border-radius:7px;font-size:27px;cursor:pointer}.mobile-drawer h2{font-size:14px;color:var(--muted);margin:24px 0 5px}.mobile-drawer>a{text-decoration:none;color:var(--title);padding:8px 10px;border-bottom:1px solid var(--line)}body.drawer-open{overflow:hidden}.nojs-nav{display:flex;flex-wrap:wrap;gap:8px;padding-block:10px}.nojs-nav a{font-size:13px;padding:4px 8px}.mobile-quick{display:flex;flex-wrap:wrap;gap:14px;padding-top:32px;font-size:14px}.mobile-quick a{text-decoration:none}}
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@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*,*:before,*:after{animation-duration:.01ms!important;transition-duration:.01ms!important}}