/* ============================================================
   Contextile · contextile.dev
   Warm-paper minimal. Modified Pagella + Noto CJK-derived subsets
   subsets, self-hosted. No frameworks, no trackers.
   ============================================================ */

/* ---------- fonts ---------- */
@font-face { font-family: "CTX Pagella"; src: url(fonts/pagella-regular.woff2) format("woff2");
  font-weight: 400; font-style: normal; font-display: swap; }
@font-face { font-family: "CTX Pagella"; src: url(fonts/pagella-italic.woff2) format("woff2");
  font-weight: 400; font-style: italic; font-display: swap; }
@font-face { font-family: "CTX Pagella"; src: url(fonts/pagella-bold.woff2) format("woff2");
  font-weight: 700; font-style: normal; font-display: swap; }
@font-face { font-family: "CTX Pagella"; src: url(fonts/pagella-bolditalic.woff2) format("woff2");
  font-weight: 700; font-style: italic; font-display: swap; }
@font-face { font-family: "CTX Serif CJK"; src: url(fonts/ctx-serif-sc.woff2) format("woff2");
  font-weight: 400; font-style: normal; font-display: swap; }
@font-face { font-family: "CTX Serif CJK"; src: url(fonts/ctx-serif-sc-bold.woff2) format("woff2");
  font-weight: 700; font-style: normal; font-display: swap; }
@font-face { font-family: "CTX Mono"; src: url(fonts/ctx-mono.woff2) format("woff2");
  font-weight: 400; font-style: normal; font-display: swap; }

/* ---------- tokens ---------- */
:root {
  --paper:   #faf9f5;
  --paper-2: #f3f1e9;
  --ink:     #14130f;
  --ink-2:   #52514e;
  --ink-3:   #8b887f;
  --line:    #e7e4da;
  --line-2:  #d6d2c4;
  --accent:  #2a5da8;
  --serif: "CTX Pagella", "CTX Serif CJK", "Songti SC", "STSong", "Noto Serif CJK SC", "SimSun", serif;
  --mono: "CTX Mono", ui-monospace, "SF Mono", Menlo, Consolas, "Noto Sans Mono CJK SC", monospace;
  --sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --w-doc: 43.5rem;
  --pad-x: clamp(20px, 5vw, 48px);
}

/* ---------- base ---------- */
* { box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition: none !important; animation: none !important; }
}
body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--serif);
  font-size: 17px;
  line-height: 1.8;
  font-kerning: normal;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}
.lang-zh { line-height: 2.05; letter-spacing: 0.012em; }
.lang-en { hyphens: auto; }
::selection { background: rgba(42, 93, 168, 0.16); }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; border-radius: 1px; }

a { color: inherit; text-decoration: underline; text-decoration-color: var(--line-2);
    text-underline-offset: 3px; text-decoration-thickness: 1px;
    transition: color .15s ease, text-decoration-color .15s ease; }
a:hover { color: var(--accent); text-decoration-color: var(--accent); }

h1, h2, h3, h4 { font-weight: 700; line-height: 1.3; margin: 0; }
p { margin: 0 0 1.45em; }
sup { font-size: .58em; color: var(--ink-3); font-family: var(--sans); margin-left: .25em; }

/* ---------- header ---------- */
.site-head {
  position: sticky; top: 0; z-index: 50;
  display: flex; align-items: center; justify-content: space-between;
  height: 60px; padding: 0 var(--pad-x);
  background: rgba(250, 249, 245, 0.86);
  -webkit-backdrop-filter: blur(10px); backdrop-filter: blur(10px);
  border-bottom: 1px solid transparent;
  transition: border-color .25s ease;
}
.site-head.scrolled { border-bottom-color: var(--line); }
.brand { display: inline-flex; align-items: center; gap: 9px;
  font-size: 17px; letter-spacing: .01em; text-decoration: none; color: var(--ink); }
.brand:hover { color: var(--ink); }
.mark rect { fill: var(--ink); }
.mark .tile-accent { fill: var(--accent); }
.site-nav { display: flex; align-items: center; gap: clamp(14px, 2.6vw, 30px); }
.site-nav a { font-family: var(--mono); font-size: 12.5px; letter-spacing: .02em;
  color: var(--ink-2); text-decoration: none; }
.site-nav a:hover { color: var(--ink); }
.site-nav a.on { color: var(--ink); border-bottom: 1px solid var(--ink); padding-bottom: 2px; }
.site-nav .ext { margin-left: 3px; color: var(--ink-3); }
.site-nav .lang { color: var(--ink-3); border: 1px solid var(--line-2); border-radius: 2px;
  padding: 3px 8px; font-family: var(--sans); font-size: 12px; }
.site-nav .lang:hover { color: var(--ink); border-color: var(--ink-2); }

/* ---------- hero ---------- */
.hero { padding: clamp(72px, 13vh, 148px) var(--pad-x) clamp(56px, 9vh, 112px);
  max-width: 68rem; margin: 0 auto; }
.hero-meta { font-family: var(--mono); font-size: 12px; letter-spacing: .14em;
  color: var(--ink-3); margin: 0 0 34px; }
.hero h1 { font-weight: 400; font-size: clamp(46px, 8.4vw, 104px);
  line-height: 1.02; letter-spacing: -0.017em; margin: 0 0 clamp(28px, 4vh, 44px); }
.tagline { font-size: clamp(20px, 2.6vw, 26px); line-height: 1.6; font-weight: 700;
  max-width: 30em; margin: 0 0 10px; }
.lang-zh .tagline { letter-spacing: .02em; }
.hero-sub { font-size: clamp(16px, 1.9vw, 18.5px); color: var(--ink-2);
  max-width: 34em; margin: 0 0 44px; }
.cta { display: flex; flex-wrap: wrap; align-items: center; gap: 14px; }
.btn { display: inline-block; font-family: var(--mono); font-size: 13px; letter-spacing: .02em;
  padding: 11px 20px; border: 1px solid var(--ink); border-radius: 2px;
  text-decoration: none; color: var(--ink); transition: all .15s ease; }
.btn:hover { background: var(--ink); color: var(--paper); }
.btn.solid { background: var(--ink); color: var(--paper); }
.btn.solid:hover { background: transparent; color: var(--ink); }
.npx { display: inline-flex; align-items: center; gap: 14px; cursor: pointer;
  font-family: var(--mono); font-size: 13px; padding: 11px 16px;
  background: transparent; border: 1px solid var(--line-2); border-radius: 2px;
  color: var(--ink-2); transition: border-color .15s ease; }
.npx:hover { border-color: var(--ink-2); }
.npx code { color: var(--ink); background: none; padding: 0; }
.npx .cp { color: var(--ink-3); font-size: 11.5px; letter-spacing: .08em; }
.npx.ok .cp { color: var(--accent); }

/* ---------- layout: toc + doc ---------- */
.layout { display: grid; grid-template-columns: 1fr; max-width: 68rem;
  margin: 0 auto; padding: 0 var(--pad-x) 40px; }
@media (min-width: 1120px) {
  .layout { grid-template-columns: 11.5rem minmax(0, var(--w-doc)); gap: clamp(48px, 6vw, 88px); }
}
.toc { display: none; }
@media (min-width: 1120px) {
  .toc { display: block; position: sticky; top: 108px; align-self: start;
    max-height: calc(100vh - 140px); overflow-y: auto; padding-bottom: 8px; }
}
.toc-label { font-family: var(--mono); font-size: 11px; letter-spacing: .18em;
  color: var(--ink-3); margin: 6px 0 14px; }
.toc ol { list-style: none; margin: 0; padding: 0; border-left: 1px solid var(--line); }
.toc li a { display: grid; grid-template-columns: 30px 1fr; align-items: baseline;
  padding: 5px 0 5px 16px; margin-left: -1px; border-left: 1px solid transparent;
  font-size: 13px; color: var(--ink-3); text-decoration: none;
  transition: color .15s ease, border-color .15s ease; }
.toc li a:hover { color: var(--ink); }
.toc li a.on { color: var(--ink); border-left-color: var(--ink); }
.toc li a.on .t-no { color: var(--accent); }
.t-no { font-family: var(--mono); font-size: 10.5px; letter-spacing: .04em; }

.toc-mobile { margin: 40px 0 8px; border: 1px solid var(--line); border-radius: 3px; }
@media (min-width: 1120px) { .toc-mobile { display: none; } }
.toc-mobile summary { font-family: var(--mono); font-size: 12.5px; letter-spacing: .14em;
  color: var(--ink-2); padding: 13px 18px; cursor: pointer; list-style: none; }
.toc-mobile summary::-webkit-details-marker { display: none; }
.toc-mobile summary::after { content: "+"; float: right; color: var(--ink-3); }
.toc-mobile[open] summary::after { content: "−"; }
.toc-mobile ol { list-style: none; margin: 0; padding: 4px 18px 16px; }
.toc-mobile a { display: grid; grid-template-columns: 34px 1fr; align-items: baseline;
  padding: 6px 0; font-size: 14px; color: var(--ink-2); text-decoration: none; }
.toc-mobile a:hover { color: var(--ink); }

/* ---------- document ---------- */
.doc { min-width: 0; }
.abstract { border-top: 2px solid var(--ink); padding-top: 34px; margin-top: 8px; }
.sec-label { font-family: var(--mono); font-size: 11.5px; letter-spacing: .2em;
  color: var(--accent); margin: 0 0 18px; }
.abstract-text { font-size: 19px; line-height: 1.95; margin: 0; }
.lang-en .abstract-text { font-size: 18.5px; line-height: 1.85; }

.chapter { border-top: 1px solid var(--line); margin-top: clamp(56px, 8vh, 88px);
  padding-top: 40px; }
.chapter[id] , .step[id], .spec-h[id] { scroll-margin-top: 92px; }
.ch-head { display: flex; align-items: baseline; gap: 18px; flex-wrap: wrap;
  margin-bottom: 30px; }
.ch-no { font-family: var(--mono); font-size: 12.5px; letter-spacing: .16em;
  color: var(--accent); }
.ch-head h2 { font-size: clamp(23px, 2.9vw, 29px); line-height: 1.45; letter-spacing: .005em; }
.lang-en .ch-head h2 { letter-spacing: -0.005em; line-height: 1.3; }

h3 { font-size: 19.5px; margin: 2.7em 0 1.1em; }
.h3-no { font-family: var(--mono); font-size: 13.5px; font-weight: 400;
  color: var(--accent); margin-right: 12px; letter-spacing: .04em; }
h4 { font-size: 17px; margin: 2.2em 0 .9em; }

.lang-zh .doc p, .lang-zh .doc li, .lang-zh .qs p, .lang-zh .qs li
  { text-align: justify; text-justify: inter-ideograph; }
.doc li, .qs li { margin: .55em 0; }
.doc ul, .doc ol, .qs ul, .qs ol { padding-left: 1.5em; margin: 1.3em 0 1.7em; }
.doc ul, .qs ul { list-style: "—  "; }
.doc li::marker, .qs li::marker { color: var(--ink-3); font-family: var(--mono); font-size: .92em; }

/* pull quotes */
blockquote { margin: 2.4em 0; padding: 0 0 0 26px; border-left: 2px solid var(--ink); }
blockquote p { margin: 0; }
blockquote.pull p { font-size: 1.16em; line-height: 1.85; }
.lang-en blockquote.pull p { font-style: italic; }
blockquote.note { border: 1px solid var(--line); border-left: 2px solid var(--line-2);
  padding: 18px 22px; font-size: 15px; line-height: 1.9; color: var(--ink-2); }
blockquote.note p { margin: 0 0 .7em; } blockquote.note p:last-child { margin: 0; }
blockquote.say { border-left: 2px solid var(--accent); }
blockquote.say p { font-size: 21px; line-height: 1.7; font-style: italic; }

/* code */
pre { font-family: var(--mono); overflow-x: auto; -webkit-overflow-scrolling: touch; }
pre.code { background: var(--paper-2); border: 1px solid var(--line); border-radius: 3px;
  padding: 20px 24px; font-size: 13.5px; line-height: 1.62; margin: 2em 0; }
pre.diagram { border: 1px solid var(--line); border-radius: 3px; padding: 22px 24px;
  font-size: 12.5px; line-height: 1.42; color: var(--ink-2); margin: 2.2em 0;
  background: transparent; }
pre code { background: none; padding: 0; font-size: inherit; }
.cm { color: var(--ink-3); }
code, kbd { font-family: var(--mono); font-size: .86em; background: var(--paper-2);
  padding: .12em .38em; border-radius: 3px; overflow-wrap: anywhere; }
pre.has-copy { position: relative; padding-top: 20px; }
.copy { position: absolute; top: 10px; right: 10px; font-family: var(--mono);
  font-size: 11px; letter-spacing: .08em; color: var(--ink-3);
  background: var(--paper); border: 1px solid var(--line); border-radius: 2px;
  padding: 4px 10px; cursor: pointer; transition: all .15s ease; }
.copy:hover { color: var(--ink); border-color: var(--ink-2); }
.copy.ok { color: var(--accent); border-color: var(--accent); }

/* tables */
.table-wrap { overflow-x: auto; margin: 2.1em 0; }
table { border-collapse: collapse; width: 100%; font-size: 15px; line-height: 1.7;
  min-width: 460px; }
th { font-family: var(--mono); font-size: 12px; font-weight: 400; letter-spacing: .06em;
  color: var(--ink-2); text-align: left; padding: 0 18px 10px 0;
  border-bottom: 1px solid var(--ink); white-space: nowrap; }
td { padding: 11px 18px 11px 0; border-bottom: 1px solid var(--line);
  vertical-align: top; }
td:last-child, th:last-child { padding-right: 0; }
table strong { white-space: nowrap; }

/* figure / chart */
figure.chart { margin: 2.8em 0; }
figure.chart svg { width: 100%; height: auto; display: block; }
.bench-chart .tick, .bench-chart .val, .bench-chart .xsub, .bench-chart .end-val
  { font-family: var(--mono) !important; }
figure.chart figcaption { font-size: 14px; line-height: 1.75; color: var(--ink-3);
  margin-top: 14px; }

/* ---------- quickstart ---------- */
.qs { max-width: var(--w-doc); margin: 0 auto; padding: 0 var(--pad-x) 40px; }
.qs-hero { padding: clamp(56px, 9vh, 104px) 0 clamp(8px, 2vh, 24px); }
.qs-hero h1 { font-size: clamp(28px, 4.4vw, 42px); font-weight: 700; line-height: 1.42;
  margin: 0 0 30px; text-wrap: balance; }
.qs-intro { font-size: 18px; line-height: 2; color: var(--ink-2); margin: 0; }
.en-note { letter-spacing: .04em; }
.step { border-top: 1px solid var(--line); margin-top: 52px; padding-top: 36px; }
.step .ch-head { margin-bottom: 22px; }
.step .ch-head h2 { font-size: 22px; }
.t-chip { font-family: var(--mono); font-size: 11.5px; color: var(--ink-3);
  border: 1px solid var(--line-2); border-radius: 999px; padding: 3px 12px; }
.next a { text-decoration-color: var(--line-2); }

/* ---------- 404 ---------- */
.nf { max-width: 68rem; margin: 0 auto; padding: 18vh var(--pad-x) 10vh; }
.nf h1 { font-weight: 400; font-size: clamp(40px, 7vw, 84px); line-height: 1.15;
  margin: 0 0 40px; }
.nf h1 span { color: var(--ink-3); }

/* ---------- footer ---------- */
.site-foot { border-top: 1px solid var(--line); margin-top: clamp(88px, 14vh, 152px); }
.foot-inner { max-width: 68rem; margin: 0 auto; padding: 64px var(--pad-x) 88px; }
.foot-mark { display: flex; align-items: center; gap: 9px; font-size: 16px;
  margin: 0 0 18px; }
.foot-rel { font-size: 15px; color: var(--ink-2); max-width: 36em; margin: 0 0 26px; }
.foot-links { display: flex; flex-wrap: wrap; gap: 22px; font-family: var(--mono);
  font-size: 12.5px; margin: 0 0 30px; }
.foot-links a { color: var(--ink-2); text-decoration: none; }
.foot-links a:hover { color: var(--accent); }
.foot-meta { font-family: var(--mono); font-size: 12px; line-height: 2;
  color: var(--ink-3); margin: 0; }
.foot-meta a { color: inherit; }

/* ---------- small screens ---------- */
@media (max-width: 640px) {
  body { font-size: 16.5px; }
  .site-nav a.on { display: none; }
  .hero { padding-top: 64px; }
  .cta .btn, .cta .npx { width: 100%; justify-content: space-between; text-align: center; }
  pre.code, pre.diagram { padding: 16px; margin-left: calc(var(--pad-x) * -0.4);
    margin-right: calc(var(--pad-x) * -0.4); }
  table { font-size: 14px; }
  .ch-head { gap: 12px; }
}

/* ---------- print ---------- */
@media print {
  .site-head, .toc, .toc-mobile, .cta, .copy, .site-foot .foot-links { display: none !important; }
  body { background: #fff; font-size: 11.5pt; }
  .chapter { border-top-color: #999; }
  a { text-decoration: none; color: inherit; }
}

/* ---------- §3 diagrams (SVG figures) ---------- */
figure.fig { margin: 2.8em 0; }
figure.fig svg { width: 100%; height: auto; display: block; }
.fig .f-name { font-family: var(--serif); font-weight: 700; fill: var(--ink); }
.fig .f-mono { font-family: var(--mono); fill: var(--ink); }
.fig .f-m2   { font-family: var(--mono); fill: var(--ink-2); }
.fig .f-m3   { font-family: var(--mono); fill: var(--ink-3); }
.fig .f-acc  { font-family: var(--mono); fill: var(--accent); }