:root{--ink:#202832;--muted:#687789;--line:#e1e5eb;--blue:#335f9f;--wash:#f7f9fb}*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;color:var(--ink);background:#fff;font:15px/1.6 system-ui,-apple-system,"Segoe UI",sans-serif}a{color:var(--blue);text-decoration:none}a:hover{text-decoration:underline}button,input,textarea{font:inherit}button{cursor:pointer}.hidden{display:none!important}.sr-only{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0,0,0,0)}.eyebrow{font-size:10px;font-weight:800;letter-spacing:1.3px;color:#70819b}
.site-header{position:sticky;top:0;z-index:10;display:flex;align-items:center;gap:35px;padding:12px clamp(16px,4vw,62px);background:#fff;border-bottom:1px solid var(--line);min-height:75px}.brand{display:flex;align-items:center;gap:13px;color:#24354b;font-size:20px;font-weight:750;white-space:nowrap;letter-spacing:-.5px}.brand:hover{text-decoration:none}.brand small{display:block;color:#91a0b5;letter-spacing:1px;font-size:9px;font-weight:750;line-height:1.2}.logo{position:relative;color:#275083;font:bold 37px/1 Georgia,serif}.logo span{position:absolute;right:-8px;top:-3px;font:12px sans-serif;color:#80a2d2}.header-search{display:flex;flex:1;max-width:700px;min-width:220px;border:1px solid #cdd6e1;border-radius:6px;overflow:hidden}.header-search input{border:0;outline:0;min-width:0;flex:1;padding:12px;font-size:14px}.header-search button{border:0;background:#315b99;color:#fff;padding:0 22px;font-weight:650}.site-nav{margin-left:auto;display:flex;gap:21px;white-space:nowrap;font-size:13px}.site-nav a{color:#50657d}.site-nav a:last-child{font-weight:700;color:#305a9b}
.home{min-height:calc(100vh - 155px);max-width:1220px;margin:auto;padding:clamp(55px,10vh,115px) 25px 50px}.home-intro{text-align:center;max-width:850px;margin:auto}.home-intro h1{font:normal clamp(37px,5vw,65px)/1.15 Georgia,serif;letter-spacing:-1.5px;margin:16px 0}.home-intro h1 em{font-weight:400;color:#315f9e}.home-intro>p{color:var(--muted);font-size:17px;max-width:650px;margin:0 auto 25px}.home-search{margin:auto;max-width:650px;display:flex;border:1px solid #bfcddd;border-radius:8px;overflow:hidden;box-shadow:0 8px 26px #17365b14}.home-search input{flex:1;min-width:0;border:0;outline:none;padding:17px;font-size:15px}.home-search button{border:0;color:#fff;background:#315b99;font-weight:650;padding:0 23px}.home-intro .search-caption{font-size:12px;color:#9aa6b4;margin:10px auto 20px}.explore-links{display:flex;flex-wrap:wrap;justify-content:center;align-items:center;gap:9px;font-size:12px}.explore-links span{color:#8492a2}.explore-links a{color:#506783;padding:6px 10px;border:1px solid #e1e6ed;border-radius:18px}.home-explainer{display:grid;grid-template-columns:repeat(3,1fr);gap:40px;border-top:1px solid var(--line);margin-top:100px;padding-top:27px}.home-explainer strong{font-size:13px;color:#415a78}.home-explainer p{font-size:13px;color:var(--muted)}
.search-layout{max-width:1260px;min-height:calc(100vh - 135px);margin:auto;display:grid;grid-template-columns:minmax(0,1fr) 290px;gap:55px;padding:45px clamp(20px,4vw,60px)}.search-main h1{font:normal 39px Georgia,serif;margin:8px 0}.search-summary{font-size:13px;color:#7a899b;margin:0 0 20px}.search-result{padding:22px 0;border-bottom:1px solid var(--line)}.search-result h2{font:normal 25px Georgia,serif;margin:0 0 6px}.search-result h2 a{color:#2b5598}.result-description{margin:0 0 8px;line-height:1.6;max-width:780px}.result-meta{display:flex;gap:12px;color:#98a4b2;font-size:11px}.read-link{display:inline-block;font-size:12px;margin-top:6px}.search-aside{padding-top:30px}.aside-panel{background:#f6f8fc;border:1px solid #e6ebf1;border-radius:11px;padding:24px}.aside-panel h2{font:normal 26px Georgia,serif;margin:13px 0}.aside-panel p{font-size:13px;color:#6e8197}.ask-link{display:inline-block;background:#315b99;color:white;padding:10px 13px;font-size:12px;border-radius:7px;margin-top:13px}.ask-link:hover{text-decoration:none;background:#244f91}.pagination{display:flex;gap:20px;margin:30px 0}.pagination button{border:1px solid #d2dfed;border-radius:7px;background:white;padding:10px 18px;color:#315b99}.search-empty{color:var(--muted)}
.article-layout{display:grid;grid-template-columns:minmax(145px,210px) minmax(0,1fr) minmax(260px,320px);max-width:1700px;margin:auto;min-height:calc(100vh - 137px)}.toc-rail{align-self:start;position:sticky;top:75px;height:calc(100vh - 75px);padding:30px 10px 20px clamp(15px,3vw,45px);overflow-y:auto;border-right:1px solid var(--line)}.toc-rail nav{margin-top:15px}.toc-rail a{display:block;padding:7px 9px;border-left:2px solid #e7edf3;font-size:12px;color:#69798c;line-height:1.4}.toc-rail a.subheading{padding-left:20px}.toc-rail a:hover{text-decoration:none;color:var(--blue);border-left-color:var(--blue)}.reader{min-width:0;padding:30px clamp(20px,3.4vw,66px) 70px}.breadcrumbs{display:flex;gap:10px;color:#8a9bad;font-size:12px;margin-bottom:24px}.page-state{color:#738398;margin:32px 0}.reader h1{font:normal clamp(36px,3.5vw,51px)/1.15 Georgia,serif;letter-spacing:-.8px;margin:8px 0 14px}.article-meta{display:flex;flex-wrap:wrap;gap:21px;color:#8a97a9;font-size:12px;padding-bottom:19px;border-bottom:1px solid var(--line);margin-bottom:25px}.wiki-content{font:16px/1.77 Georgia,"Times New Roman",serif;overflow-wrap:anywhere}.wiki-content p{margin:0 0 17px}.wiki-content h2,.wiki-content h3,.wiki-content h4{scroll-margin-top:95px;font-family:Georgia,serif;font-weight:400;line-height:1.25}.wiki-content h2{font-size:30px;border-bottom:1px solid var(--line);padding-bottom:9px;margin:39px 0 17px}.wiki-content h3{font-size:24px;margin:27px 0 13px}.wiki-content img{height:auto;max-width:100%}.wiki-content figure{max-width:100%;margin:14px}.wiki-content figcaption{font:11px/1.5 sans-serif;color:#8795a4}.wiki-content table{display:block;max-width:100%;overflow-x:auto;border-collapse:collapse;font:12px/1.45 sans-serif;margin:17px 0}.wiki-content td,.wiki-content th{padding:7px 9px;border:1px solid #dbe1e8;vertical-align:top}.wiki-content th{background:#f2f4f6}.wiki-content .infobox{float:right;max-width:310px;margin:0 0 20px 18px;background:#f7f9fb;border:1px solid #dce4ef;padding:10px}.wiki-content pre{white-space:pre-wrap}.wiki-content sup{font:11px sans-serif}.attribution{border-top:1px solid var(--line);font-size:11px;color:#8998a8;margin-top:65px;padding:17px 0}.attribution p{margin:5px 0}
.ask-sidebar{border-left:1px solid var(--line);align-self:start;position:sticky;top:75px;height:calc(100vh - 75px);padding:26px 19px 20px;background:#fafcff;display:flex;flex-direction:column}.assistant-top{display:flex;gap:12px;align-items:center;padding-bottom:19px;border-bottom:1px solid var(--line)}.assistant-symbol{width:38px;height:38px;display:grid;place-items:center;background:#e8f1ff;border-radius:10px;color:#3165ad;font-size:21px}.assistant-top strong{font-size:14px;display:block}.assistant-top small{display:block;color:#95a1b1;font-size:11px}.assistant-description{font-size:12px;color:#7a8a9f;line-height:1.6}.article-chat{flex:1;overflow-y:auto;min-height:60px}.ask-form{padding:11px;background:#fff;border:1px solid #d9e3ee;border-radius:10px;margin-top:10px}.ask-form:focus-within{border-color:#80a5d7}.ask-form textarea{width:100%;border:0;resize:vertical;outline:none;font:13px/1.55 system-ui,sans-serif;min-height:65px}.form-bottom{display:flex;align-items:center;justify-content:space-between;gap:8px}.form-bottom span{font-size:10px;color:#9aa7b7}.form-bottom button{border:0;border-radius:7px;background:#315b99;color:#fff;font-size:12px;font-weight:700;padding:9px 14px}.form-bottom button:disabled{opacity:.5;cursor:wait}.disclaimer{font-size:10px;color:#9aa5b3;padding-top:13px}.question-bubble{font-size:14px;color:#233e62;background:#ecf3ff;border-radius:11px;padding:12px;margin:13px 0}.loading-bubble{font-size:12px;color:#8b9cb2;margin:15px 0}.answer{font-size:14px;line-height:1.75;overflow-wrap:anywhere}.answer p{margin:12px 0}.answer h3{font-size:19px;font-weight:650;margin:19px 0 8px}.answer h4{font-size:16px;margin:17px 0 7px}.answer ul,.answer ol{padding-left:23px}.answer li{margin:6px 0}.answer-table{width:100%;border-collapse:collapse;font:13px/1.6 system-ui,sans-serif;display:block;overflow-x:auto;margin:12px 0}.answer-table th,.answer-table td{border:1px solid #dee5ef;padding:7px 9px}.answer-table th{background:#f4f7fb}.cite{font-size:11px;font-weight:800;margin:0 2px}.error{color:#a53737;font-size:13px}
.ask-layout{max-width:820px;min-height:calc(100vh - 140px);margin:auto;padding:45px 22px 70px}.ask-header h1{font:normal 42px Georgia,serif;margin:9px 0}.ask-header p{color:#71839b;max-width:660px}.chat{margin:28px 0 16px}.chat .question-bubble{font:normal 27px Georgia,serif;background:none;border-bottom:1px solid var(--line);padding:25px 0}.chat .answer{padding:6px 0 24px;border-bottom:1px solid var(--line)}.wide-ask-form{margin-top:24px}.wide-ask-form textarea{font-size:15px;min-height:80px}.ask-sources{margin-top:35px}.ask-sources h2{font:normal 27px Georgia,serif}.source-card{border:1px solid #e1e8ef;display:block;border-radius:9px;padding:13px 16px;margin:9px 0}.source-card strong{display:block;color:#294e84;font-size:14px}.source-card small{display:block;color:#8491a1}.footer{border-top:1px solid var(--line);padding:22px;text-align:center;color:#98a5b5;font-size:10px}
@media(max-width:1150px){.article-layout{grid-template-columns:160px minmax(0,1fr)}.ask-sidebar{position:static;height:auto;min-height:330px;grid-column:2;border-left:0;border-top:1px solid var(--line)}.article-chat{max-height:450px}.site-header{gap:15px}}@media(max-width:760px){.site-header{flex-wrap:wrap;padding:12px 17px;gap:9px;min-height:0}.brand{font-size:17px}.logo{font-size:30px}.site-nav{font-size:11px;gap:10px}.header-search{order:3;max-width:none;flex:0 0 100%;min-width:0}.header-search input{padding:10px}.header-search button{padding:0 13px}.home{padding:62px 18px 35px}.home-intro h1{font-size:41px;letter-spacing:-1px}.home-intro>p{font-size:15px}.home-explainer{display:block;margin-top:72px}.home-explainer div{padding:8px 0}.search-layout{display:block;padding:31px 20px}.search-aside{padding:10px 0 25px}.article-layout{display:block}.toc-rail{display:none}.reader{padding:26px 19px 45px}.wiki-content .infobox{float:none;max-width:100%;margin:14px 0}.ask-sidebar{padding:21px;height:auto;min-height:360px}.ask-layout{padding:32px 19px}.ask-header h1{font-size:34px}}

/* Keep the article as the only primary scroll area; on tablets and phones the
   optional question panel opens on demand rather than sitting after a long page. */
.mobile-ask-trigger,.mobile-ask-close,.mobile-ask-backdrop{display:none}
.mobile-ask-backdrop[hidden]{display:none!important}
html{scroll-padding-top:100px}
@media(max-width:1150px){
  .reader{padding-bottom:106px}
  .mobile-ask-trigger{
    display:flex;align-items:center;justify-content:center;gap:8px;
    position:fixed;bottom:calc(18px + env(safe-area-inset-bottom,0px));right:18px;
    z-index:35;min-height:46px;padding:12px 19px;border:0;border-radius:999px;
    background:#315b99;color:#fff;font-size:14px;font-weight:750;
    box-shadow:0 7px 24px #18396042
  }
  .mobile-ask-trigger:hover{background:#244b86}
  .article-layout .ask-sidebar{
    display:none;position:fixed;inset:auto 16px 16px auto;z-index:51;
    width:min(440px,calc(100vw - 32px));height:min(78dvh,690px);min-height:0;
    max-height:calc(100dvh - 32px);padding:21px;background:#fff;
    border:1px solid #dfe6ee;border-radius:16px;
    box-shadow:0 25px 90px #172b4c44;
    flex-direction:column
  }
  .article-layout .ask-sidebar.mobile-open{display:flex}
  .mobile-ask-backdrop:not([hidden]){
    display:block;position:fixed;inset:0;background:#071b38a6;z-index:50
  }
  .mobile-ask-close{
    display:grid;place-items:center;margin-left:auto;border:0;background:#f0f3f8;
    border-radius:8px;width:38px;height:38px;font-size:23px;color:#506480
  }
  .article-chat{flex:1;min-height:20px;overflow-y:auto;overscroll-behavior:contain;max-height:none}
  .ask-form{flex-shrink:0}
  body.mobile-ask-open{overflow:hidden}
}
@media(max-width:760px){
  html{scroll-padding-top:145px}
  .site-header{z-index:9;row-gap:11px}
  .site-nav a{min-height:38px;display:inline-flex;align-items:center}
  .header-search input{min-height:43px}
  .header-search button{min-width:76px}
  .reader{padding:23px 17px 110px}
  .reader h1{font-size:clamp(32px,9vw,42px)}
  .wiki-content{font-size:16px;line-height:1.72}
  .wiki-content h2{font-size:26px}
  .wiki-content h3{font-size:21px}
  .wiki-content table{font-size:12px}
  .wiki-content figure{max-width:100%;margin:15px 0}
  .wiki-content blockquote{margin:16px 0;padding:0 13px;border-left:3px solid #dce6f1}
  .wiki-content h2,.wiki-content h3,.wiki-content h4{scroll-margin-top:145px}
  .article-layout .ask-sidebar{
    inset:auto 0 0 0;width:100%;height:min(82dvh,760px);max-height:92dvh;
    border-radius:19px 19px 0 0;border:1px solid #dfe6ee;
    padding:20px 17px calc(16px + env(safe-area-inset-bottom,0px))
  }
  .mobile-ask-trigger{right:15px;bottom:calc(17px + env(safe-area-inset-bottom,0px))}
  .assistant-description{margin:14px 0}
  .article-chat{font-size:14px}
  .ask-form textarea{min-height:68px}
  .form-bottom button{min-height:42px}
}