:root{
  --paper:#F4F1EA; --paper-2:#EDE9E0; --paper-3:#E6E2D8;
  --ink:#1C1A14; --char:#454136; --mut:#7C7668;
  --line:rgba(28,26,20,.16); --line-strong:rgba(28,26,20,.34);
  --red:#C2401C;
  --sans:"Archivo",-apple-system,BlinkMacSystemFont,"Helvetica Neue",Helvetica,Arial,sans-serif;
  --mono:"IBM Plex Mono",ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;
  --sb:264px; --toc:212px; --bar:56px;
  color-scheme:light;
}
@media (prefers-color-scheme:dark){
  :root:not([data-theme="light"]){
    --paper:#131210; --paper-2:#1A1815; --paper-3:#232019;
    --ink:#EDEAE1; --char:#C6C1B4; --mut:#8C8678;
    --line:rgba(237,234,225,.14); --line-strong:rgba(237,234,225,.3);
    --red:#E4693F;
    color-scheme:dark;
  }
}
:root[data-theme="dark"]{
  --paper:#131210; --paper-2:#1A1815; --paper-3:#232019;
  --ink:#EDEAE1; --char:#C6C1B4; --mut:#8C8678;
  --line:rgba(237,234,225,.14); --line-strong:rgba(237,234,225,.3);
  --red:#E4693F; color-scheme:dark;
}
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth;scroll-padding-top:calc(var(--bar) + 18px)}
@media (prefers-reduced-motion:reduce){html{scroll-behavior:auto}}
body{margin:0;background:var(--paper);color:var(--ink);font-family:var(--sans);
  font-size:16px;line-height:1.65;-webkit-font-smoothing:antialiased;overflow-x:hidden}
a{color:inherit}
img{max-width:100%;height:auto}
.skip{position:absolute;left:-9999px;top:0;background:var(--ink);color:var(--paper);
  padding:10px 16px;z-index:100}
.skip:focus{left:8px;top:8px}

/* ---------- top bar ---------- */
.topbar{position:sticky;top:0;z-index:40;height:var(--bar);display:flex;align-items:center;
  gap:16px;padding:0 clamp(14px,2.4vw,24px);background:color-mix(in srgb,var(--paper) 88%,transparent);
  backdrop-filter:saturate(140%) blur(10px);border-bottom:1px solid var(--line)}
.brand{display:flex;align-items:baseline;gap:8px;text-decoration:none;flex:0 0 auto}
.brand-mark{font-weight:700;letter-spacing:.16em;font-size:15px}
.brand-sub{font-family:var(--mono);font-size:11px;color:var(--mut);letter-spacing:.14em;
  text-transform:uppercase}
.topnav{margin-left:auto;display:flex;gap:20px;flex:0 0 auto}
.topnav a{font-size:13.5px;color:var(--char);text-decoration:none}
.topnav a:hover{color:var(--ink)}
.menu-btn{display:none;flex-direction:column;gap:4px;width:34px;height:34px;padding:8px;
  border:1px solid var(--line);border-radius:7px;background:none;cursor:pointer}
.menu-btn span{display:block;height:1.5px;background:var(--ink);border-radius:2px}

/* ---------- header tools: language + theme ---------- */
.tools{margin-left:auto;display:flex;align-items:center;gap:8px;flex:0 0 auto}
.topnav{display:flex;gap:18px;margin-left:6px}
.theme-toggle{display:grid;place-items:center;width:34px;height:34px;padding:0;
  border:1px solid var(--line);border-radius:8px;background:none;cursor:pointer;color:var(--char)}
.theme-toggle:hover{color:var(--ink);border-color:var(--line-strong)}
.theme-toggle svg{width:17px;height:17px;display:none;fill:none;stroke:currentColor;
  stroke-width:1.6;stroke-linecap:round;stroke-linejoin:round}
[data-theme="light"] .theme-toggle .icon-moon{display:block}
[data-theme="dark"] .theme-toggle .icon-sun{display:block}
html:not([data-theme]) .theme-toggle .icon-moon{display:block}

.lang-wrap{position:relative}
.lang-btn{display:flex;align-items:center;gap:6px;height:34px;padding:0 10px;
  font:inherit;font-family:var(--mono);font-size:11.5px;letter-spacing:.08em;
  color:var(--char);background:none;border:1px solid var(--line);border-radius:8px;cursor:pointer}
.lang-btn:hover{color:var(--ink);border-color:var(--line-strong)}
.lang-btn svg{width:15px;height:15px;fill:none;stroke:currentColor;stroke-width:1.5}
.lang-menu{position:absolute;top:calc(100% + 7px);right:0;width:210px;max-height:min(70vh,420px);
  overflow:auto;padding:5px;background:var(--paper);border:1px solid var(--line-strong);
  border-radius:10px;box-shadow:0 18px 44px rgba(28,26,20,.18);z-index:60}
.lang-opt{display:flex;align-items:center;gap:9px;padding:7px 10px;border-radius:7px;
  font-size:13.5px;color:var(--char);text-decoration:none}
.lang-opt:hover{background:var(--paper-2);color:var(--ink)}
.lang-opt i{font-family:var(--mono);font-size:10px;font-style:normal;letter-spacing:.1em;
  color:var(--mut);min-width:20px}
.lang-opt.is-current{color:var(--ink);font-weight:600}
.lang-opt.is-current i{color:var(--red)}
.lang-opt.untranslated{opacity:.55}
:lang(zh),:lang(ja),:lang(ko){font-family:"Noto Sans SC","Noto Sans JP","Noto Sans KR",var(--sans)}

/* ---------- search ---------- */
.search{position:relative;flex:1 1 auto;max-width:420px;min-width:0}
.search input{width:100%;height:34px;padding:0 12px;font:inherit;font-size:13.5px;
  color:var(--ink);background:var(--paper-2);border:1px solid var(--line);border-radius:8px}
.search input:focus{outline:none;border-color:var(--line-strong);background:var(--paper)}
.results{position:absolute;top:calc(100% + 7px);left:0;right:0;max-height:min(66vh,460px);
  overflow:auto;background:var(--paper);border:1px solid var(--line-strong);border-radius:10px;
  box-shadow:0 18px 44px rgba(28,26,20,.16);padding:5px;z-index:50}
.results a{display:block;padding:9px 11px;border-radius:7px;text-decoration:none}
.results a:hover,.results a.sel{background:var(--paper-2)}
.results b{display:block;font-size:13.5px;font-weight:600}
.results span{display:block;font-size:12px;color:var(--mut);overflow:hidden;
  text-overflow:ellipsis;white-space:nowrap}
.results .empty{padding:14px;font-size:13px;color:var(--mut)}

/* ---------- shell ---------- */
.shell{display:grid;grid-template-columns:var(--sb) minmax(0,1fr) var(--toc);
  align-items:start;max-width:1480px;margin:0 auto}
.sidebar{position:sticky;top:var(--bar);height:calc(100svh - var(--bar));overflow-y:auto;
  padding:22px 12px 40px clamp(14px,2.4vw,24px);border-right:1px solid var(--line);min-width:0}
.nav{display:flex;flex-direction:column;gap:1px}
.nav-group{margin:20px 0 7px;padding:0 10px;font-family:var(--mono);font-size:10.5px;
  letter-spacing:.16em;text-transform:uppercase;color:var(--mut)}
.nav-group:first-child{margin-top:0}
.nav-link{display:block;padding:6px 10px;border-radius:7px;font-size:14px;color:var(--char);
  text-decoration:none;border-left:2px solid transparent}
.nav-link:hover{background:var(--paper-2);color:var(--ink)}
.nav-link.is-current{background:var(--paper-2);color:var(--ink);font-weight:600;
  border-left-color:var(--red)}
.nav-link.lvl-1{padding-left:24px;font-size:13.5px}
.nav-link.lvl-2{padding-left:38px;font-size:13px}
.scrim{position:fixed;inset:0;background:rgba(28,26,20,.4);z-index:29}

.main{min-width:0;padding:26px clamp(18px,3.6vw,52px) 72px;max-width:none}
.crumbs{display:flex;flex-wrap:wrap;gap:7px;align-items:center;font-family:var(--mono);
  font-size:11.5px;color:var(--mut);margin-bottom:16px}
.crumbs a{text-decoration:none}.crumbs a:hover{color:var(--ink)}
.crumbs .sep{opacity:.5}

/* ---------- prose ---------- */
.prose{max-width:74ch}
.prose h1{font-size:clamp(29px,3.6vw,40px);line-height:1.14;letter-spacing:-.022em;
  font-weight:700;margin:0 0 18px}
.prose h2{font-size:clamp(21px,2.2vw,26px);line-height:1.26;letter-spacing:-.014em;
  font-weight:650;margin:46px 0 12px;padding-top:14px;border-top:1px solid var(--line)}
.prose h3{font-size:17.5px;font-weight:650;margin:30px 0 9px}
.prose h4{font-size:15.5px;font-weight:650;margin:24px 0 7px;color:var(--char)}
.prose p{margin:0 0 15px;color:var(--char)}
.prose>p:first-of-type{font-size:17.5px;line-height:1.6;color:var(--ink)}
.prose a{color:var(--ink);text-decoration:underline;text-decoration-color:var(--line-strong);
  text-underline-offset:3px;text-decoration-thickness:1px}
.prose a:hover{text-decoration-color:var(--red);color:var(--red)}
.prose strong{font-weight:650;color:var(--ink)}
.prose ul,.prose ol{margin:0 0 15px;padding-left:22px;color:var(--char)}
.prose li{margin:5px 0}
.prose li::marker{color:var(--mut)}
.prose ul.contains-task-list{list-style:none;padding-left:2px}
.prose hr{border:0;border-top:1px solid var(--line);margin:34px 0}
.prose blockquote{margin:0 0 18px;padding:2px 0 2px 18px;border-left:2px solid var(--red);
  color:var(--char);font-style:italic}
.prose blockquote p:last-child{margin-bottom:0}
.anchor{margin-left:9px;color:var(--mut);text-decoration:none;opacity:0;font-weight:400;
  font-family:var(--mono);font-size:.72em}
h1:hover .anchor,h2:hover .anchor,h3:hover .anchor,h4:hover .anchor{opacity:.6}
.anchor:hover{opacity:1!important;color:var(--red)}

.prose :not(pre)>code{font-family:var(--mono);font-size:.87em;padding:.14em .4em;
  background:var(--paper-3);border:1px solid var(--line);border-radius:5px;
  word-break:break-word}
.code-block{position:relative;margin:0 0 20px;background:var(--paper-2);
  border:1px solid var(--line);border-radius:10px;overflow:hidden}
.code-lang{position:absolute;top:0;right:0;padding:4px 11px;font-family:var(--mono);
  font-size:10px;letter-spacing:.12em;text-transform:uppercase;color:var(--mut);
  border-left:1px solid var(--line);border-bottom:1px solid var(--line);
  border-bottom-left-radius:8px}
.code-block pre{margin:0;padding:16px 18px;overflow-x:auto;font-family:var(--mono);
  font-size:13px;line-height:1.7}
.code-block code{font-family:inherit}
.copy{position:absolute;top:7px;right:8px;padding:4px 9px;font-family:var(--mono);
  font-size:10.5px;letter-spacing:.08em;text-transform:uppercase;color:var(--mut);
  background:var(--paper);border:1px solid var(--line);border-radius:6px;cursor:pointer;
  opacity:0;transition:opacity .14s}
.code-block:hover .copy,.copy:focus{opacity:1}
.copy:hover{color:var(--ink);border-color:var(--line-strong)}
.code-block:has(.copy) .code-lang{display:none}

.table-wrap{overflow-x:auto;margin:0 0 20px;border:1px solid var(--line);border-radius:10px}
table{border-collapse:collapse;width:100%;font-size:14px}
th,td{padding:10px 14px;text-align:left;border-bottom:1px solid var(--line)}
th{font-weight:650;background:var(--paper-2);white-space:nowrap}
tbody tr:last-child td{border-bottom:0}

.hint{margin:0 0 20px;padding:14px 16px;border:1px solid var(--line);border-left-width:3px;
  border-radius:9px;background:var(--paper-2);font-size:14.5px}
.hint p:last-child{margin-bottom:0}
.hint-info{border-left-color:#3B6EA5}
.hint-success{border-left-color:#2E7D5B}
.hint-warning{border-left-color:#B07A1E}
.hint-danger{border-left-color:var(--red)}

/* ---------- pager + toc ---------- */
.pager-row{display:grid;grid-template-columns:repeat(auto-fit,minmax(210px,1fr));gap:12px;
  max-width:74ch;margin:54px 0 0}
.pager{padding:13px 16px;border:1px solid var(--line);border-radius:10px;text-decoration:none;
  background:var(--paper-2)}
.pager:hover{border-color:var(--line-strong);background:var(--paper)}
.pager span{display:block;font-family:var(--mono);font-size:10.5px;letter-spacing:.14em;
  text-transform:uppercase;color:var(--mut);margin-bottom:3px}
.pager b{font-size:14.5px;font-weight:600}
.pager.next{text-align:right}
.foot{max-width:74ch;margin-top:44px;padding-top:18px;border-top:1px solid var(--line);
  font-family:var(--mono);font-size:11.5px;color:var(--mut)}

.toc{position:sticky;top:var(--bar);max-height:calc(100svh - var(--bar));overflow-y:auto;
  padding:26px 20px 40px 8px;min-width:0}
.toc-head{font-family:var(--mono);font-size:10.5px;letter-spacing:.16em;text-transform:uppercase;
  color:var(--mut);margin-bottom:9px}
.toc a{display:block;padding:4px 0 4px 11px;font-size:13px;color:var(--mut);
  text-decoration:none;border-left:1.5px solid var(--line)}
.toc a:hover{color:var(--ink)}
.toc a.active{color:var(--ink);border-left-color:var(--red)}
.toc .toc-l3{padding-left:24px;font-size:12.5px}

/* ---------- responsive ---------- */
@media (max-width:1180px){
  .shell{grid-template-columns:var(--sb) minmax(0,1fr)}
  .toc{display:none}
}
@media (max-width:860px){
  .shell{grid-template-columns:minmax(0,1fr)}
  .menu-btn{display:flex}
  .topnav{display:none}
  .topbar{gap:9px;padding:0 12px}
  .brand-sub{display:none}
  .lang-btn span{display:none}
  .lang-btn{padding:0 9px}
  .lang-menu{width:190px}
  .sidebar{position:fixed;top:var(--bar);left:0;width:min(86vw,var(--sb));z-index:30;
    background:var(--paper);transform:translateX(-102%);transition:transform .2s ease;
    border-right:1px solid var(--line-strong)}
  body.nav-open .sidebar{transform:none}
  .scrim[hidden]{display:none}
  .main{padding:20px 18px 60px}
}
@media (max-width:480px){
  .brand-mark{font-size:14px}
  .search input{font-size:16px}   /* 16px stops iOS zooming the page on focus */
}
@media (prefers-reduced-motion:reduce){.sidebar{transition:none}}
@media print{
  .topbar,.sidebar,.toc,.pager-row,.scrim{display:none!important}
  .shell{display:block}.main{padding:0}
}