/* ==========================================================
   CCA Study Hub — shared styles for every page
   ========================================================== */
:root {
  --bg: #faf9f6;
  --surface: #ffffff;
  --surface-2: #f2f0eb;
  --border: #e3e0d8;
  --text: #1f1e1c;
  --muted: #6b675f;
  --accent: #c2410c;
  --accent-soft: #fdeee6;
  --link: #9a3412;
  --code-bg: #f4f2ed;
  --code-text: #2b2a27;
  --ok: #15803d;   --ok-soft: #e8f5ec;
  --warn: #b45309; --warn-soft: #fdf3e2;
  --bad: #b91c1c;  --bad-soft: #fbeaea;
  --info: #1d4ed8; --info-soft: #e9effc;
  --sidebar-w: 290px;
  --radius: 10px;
  --font: "Inter", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  --mono: "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #161514; --surface: #1e1d1b; --surface-2: #262522; --border: #35332f;
    --text: #ecebe7; --muted: #a29e95; --accent: #fb923c; --accent-soft: #3a2518;
    --link: #fdba74; --code-bg: #24231f; --code-text: #e7e5df;
    --ok: #4ade80; --ok-soft: #15291c; --warn: #fbbf24; --warn-soft: #2f2612;
    --bad: #f87171; --bad-soft: #321818; --info: #93b4fd; --info-soft: #18223a;
  }
}
:root[data-theme="dark"] {
  --bg: #161514; --surface: #1e1d1b; --surface-2: #262522; --border: #35332f;
  --text: #ecebe7; --muted: #a29e95; --accent: #fb923c; --accent-soft: #3a2518;
  --link: #fdba74; --code-bg: #24231f; --code-text: #e7e5df;
  --ok: #4ade80; --ok-soft: #15291c; --warn: #fbbf24; --warn-soft: #2f2612;
  --bad: #f87171; --bad-soft: #321818; --info: #93b4fd; --info-soft: #18223a;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 76px; }
body {
  margin: 0; background: var(--bg); color: var(--text);
  font: 16px/1.65 var(--font); -webkit-font-smoothing: antialiased;
}
a { color: var(--link); text-underline-offset: 2px; }
h1, h2, h3, h4 { line-height: 1.25; letter-spacing: -0.01em; }
h1 { font-size: 2.1rem; margin: 0 0 .4rem; }
h2 { font-size: 1.55rem; margin: 3rem 0 1rem; padding-top: 1.2rem; border-top: 1px solid var(--border); }
h3 { font-size: 1.15rem; margin: 1.8rem 0 .6rem; }
h4 { font-size: 1rem; margin: 1.2rem 0 .4rem; }
p, ul, ol { margin: 0 0 1rem; }
li { margin: .25rem 0; }
code {
  font-family: var(--mono); font-size: .86em; background: var(--code-bg);
  color: var(--code-text); padding: .12em .38em; border-radius: 5px; border: 1px solid var(--border);
  overflow-wrap: anywhere;   /* long inline snippets wrap instead of widening the page */
}
pre {
  position: relative; background: var(--code-bg); color: var(--code-text);
  border: 1px solid var(--border); border-radius: var(--radius);
  padding: 1rem 1.1rem; overflow-x: auto; font: 13.5px/1.55 var(--mono); margin: 0 0 1.2rem;
}
pre code { background: none; border: 0; padding: 0; font-size: inherit; }
pre .c { color: var(--muted); font-style: italic; }
pre .k { color: var(--accent); font-weight: 600; }
.copy-btn {
  position: absolute; top: 8px; right: 8px; font: 12px var(--font);
  background: var(--surface); color: var(--muted); border: 1px solid var(--border);
  border-radius: 6px; padding: 2px 8px; cursor: pointer; opacity: 0; transition: opacity .15s;
}
pre:hover .copy-btn, .copy-btn:focus { opacity: 1; }

/* ---------- Layout ---------- */
.topbar {
  position: sticky; top: 0; z-index: 30; height: 60px; display: flex; align-items: center; gap: 12px;
  padding: 0 16px; background: var(--bg);  /* solid fallback for browsers without color-mix */
  background: color-mix(in srgb, var(--bg) 92%, transparent);
  -webkit-backdrop-filter: blur(8px); backdrop-filter: blur(8px); border-bottom: 1px solid var(--border);
}
.brand { display: flex; align-items: center; gap: 10px; font-weight: 700; color: var(--text); text-decoration: none; }
.brand-mark {
  width: 30px; height: 30px; border-radius: 8px; background: var(--accent); color: #fff;
  display: grid; place-items: center; font-size: 14px; font-weight: 800;
}
.brand small { display: block; font-weight: 500; color: var(--muted); font-size: 12px; line-height: 1; }
.topbar .spacer { flex: 1; }
.icon-btn {
  border: 1px solid var(--border); background: var(--surface); color: var(--text);
  border-radius: 8px; height: 36px; min-width: 36px; padding: 0 10px; cursor: pointer; font: 14px var(--font);
}
.menu-btn { display: none; }

.layout { display: grid; grid-template-columns: var(--sidebar-w) minmax(0, 1fr) 220px; max-width: 1480px; margin: 0 auto; }
.sidebar {
  position: sticky; top: 60px; height: calc(100vh - 60px); overflow-y: auto;
  padding: 18px 14px 40px; border-right: 1px solid var(--border);
}
.search {
  width: 100%; padding: 8px 12px; border-radius: 8px; border: 1px solid var(--border);
  background: var(--surface); color: var(--text); font: 14px var(--font); margin-bottom: 14px;
}
.nav-group { font-size: 11px; text-transform: uppercase; letter-spacing: .08em; color: var(--muted); margin: 16px 8px 6px; font-weight: 700; }
.nav-topic {
  display: flex; align-items: center; gap: 8px; padding: 7px 10px; border-radius: 8px;
  color: var(--text); text-decoration: none; font-weight: 600; font-size: 14.5px;
}
.nav-topic:hover { background: var(--surface-2); }
.nav-topic.active { background: var(--accent-soft); color: var(--accent); }
.nav-topic .badge { white-space: nowrap; flex: none; margin-left: auto; font-size: 10.5px; font-weight: 600; color: var(--muted); border: 1px solid var(--border); border-radius: 99px; padding: 0 7px; }
.nav-topic.soon { color: var(--muted); font-weight: 500; pointer-events: none; }
.nav-sections { list-style: none; margin: 4px 0 8px 14px; padding: 0 0 0 10px; border-left: 1px solid var(--border); }
.nav-sections li { margin: 0; }
.nav-sections a {
  display: flex; gap: 6px; align-items: baseline; padding: 4px 8px; border-radius: 6px;
  color: var(--muted); text-decoration: none; font-size: 13.5px;
}
.nav-sections a:hover { color: var(--text); background: var(--surface-2); }
.nav-sections a.current { color: var(--accent); font-weight: 600; }
.nav-sections a .done { color: var(--ok); font-size: 11px; }

main { padding: 32px 48px 80px; min-width: 0; }
/* Before site.js builds the shell (or if scripts are blocked), still centre the article */
body > main { max-width: 960px; margin: 0 auto; }
pre, .table-wrap, .diagram { max-width: 100%; }
.content { max-width: 860px; }
.toc { position: sticky; top: 60px; height: calc(100vh - 60px); overflow-y: auto; padding: 32px 16px; font-size: 13px; }
.toc h5 { margin: 0 0 8px; font-size: 11px; text-transform: uppercase; letter-spacing: .08em; color: var(--muted); }
.toc a { display: block; color: var(--muted); text-decoration: none; padding: 3px 0; }
.toc a:hover, .toc a.current { color: var(--accent); }

/* ---------- Components ---------- */
.eyebrow { color: var(--accent); font-weight: 700; font-size: 13px; text-transform: uppercase; letter-spacing: .08em; }
.lede { font-size: 1.12rem; color: var(--muted); max-width: 70ch; }
.meta-row { display: flex; flex-wrap: wrap; gap: 8px; margin: 1rem 0 1.5rem; }
.pill { font-size: 12.5px; border: 1px solid var(--border); background: var(--surface); border-radius: 99px; padding: 3px 10px; color: var(--muted); }
.pill b { color: var(--text); }

.callout { border: 1px solid var(--border); border-left: 4px solid var(--info); background: var(--info-soft); border-radius: var(--radius); padding: .85rem 1rem; margin: 0 0 1.2rem; }
.callout > :last-child { margin-bottom: 0; }
.callout .title { display: block; font-weight: 700; margin-bottom: .25rem; }
.callout.exam { border-left-color: var(--accent); background: var(--accent-soft); }
.callout.trap { border-left-color: var(--bad); background: var(--bad-soft); }
.callout.tip  { border-left-color: var(--ok); background: var(--ok-soft); }
.callout.warn { border-left-color: var(--warn); background: var(--warn-soft); }

.table-wrap { overflow-x: auto; margin: 0 0 1.2rem; border: 1px solid var(--border); border-radius: var(--radius); }
table { border-collapse: collapse; width: 100%; font-size: 14.5px; background: var(--surface); }
th, td { text-align: left; padding: .55rem .8rem; border-bottom: 1px solid var(--border); vertical-align: top; }
th { background: var(--surface-2); font-size: 12.5px; text-transform: uppercase; letter-spacing: .04em; color: var(--muted); }
tr:last-child td { border-bottom: 0; }
td code { white-space: nowrap; }

.grid { display: grid; gap: 14px; grid-template-columns: repeat(auto-fill, minmax(240px, 1fr)); margin: 0 0 1.2rem; }
.card { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 1rem 1.1rem; }
.card h4 { margin-top: 0; }
.card p:last-child { margin-bottom: 0; }
a.card { text-decoration: none; color: var(--text); transition: border-color .15s, transform .15s; display: block; }
a.card:hover { border-color: var(--accent); transform: translateY(-2px); }
.card.disabled { opacity: .6; }

.diagram { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 1rem; margin: 0 0 1.2rem; }
.diagram svg { width: 100%; height: auto; display: block; }
.diagram.narrow svg { max-width: 440px; margin: 0 auto; }   /* tall diagrams shouldn't fill the column */
.diagram figcaption { font-size: 13px; color: var(--muted); margin-top: .5rem; text-align: center; }
.diagram svg text { font-family: var(--font); fill: var(--text); }
.diagram svg .box { fill: var(--surface-2); stroke: var(--border); }
.diagram svg .box-accent { fill: var(--accent-soft); stroke: var(--accent); }
.diagram svg .box-ok { fill: var(--ok-soft); stroke: var(--ok); }
.diagram svg .line { stroke: var(--muted); fill: none; stroke-width: 1.6; }
.diagram svg .line-accent { stroke: var(--accent); fill: none; stroke-width: 1.8; }
.diagram svg .lbl { fill: var(--muted); font-size: 12px; }
.diagram svg .lbl-accent { fill: var(--accent); font-size: 12px; font-weight: 700; }
.diagram svg .lbl-ok { fill: var(--ok); font-size: 12px; font-weight: 700; }
.diagram svg .box-info { fill: var(--info-soft); stroke: var(--info); }
.diagram svg .zone { fill: none; stroke: var(--border); stroke-width: 1.5; stroke-dasharray: 6 5; }
.diagram svg .dash { stroke-dasharray: 5 4; }

/* Animated SVG diagrams (SMIL): moving coins + a play/pause button in the caption */
.diagram svg .coin { fill: var(--accent); stroke: var(--surface); stroke-width: 2; }
.diagram svg .coin-ok { fill: var(--ok); stroke: var(--surface); stroke-width: 2; }
.diagram svg .coin-info { fill: var(--info); stroke: var(--surface); stroke-width: 2; }
.diagram svg .coin-text { fill: var(--bg); font-size: 11px; font-weight: 800; }
.diagram svg .box-bad { fill: var(--bad-soft); stroke: var(--bad); }
.diagram svg .lbl-bad { fill: var(--bad); font-size: 12px; font-weight: 700; }
.diagram svg .line-ok { stroke: var(--ok); fill: none; stroke-width: 1.8; }
.diagram svg .line-bad { stroke: var(--bad); fill: none; stroke-width: 1.8; }
.diagram svg .mono { font-family: var(--mono); font-size: 11.5px; }
.diagram svg .light-red { fill: var(--bad); }
.diagram svg .light-green { fill: var(--ok); }
.anim-btn {
  font: 12px var(--font); color: var(--text); background: var(--surface-2); border: 1px solid var(--border);
  border-radius: 6px; padding: 1px 8px; margin-right: 8px; cursor: pointer; vertical-align: 1px;
}
.anim-btn:hover { border-color: var(--accent); }

/* Result banner + trace for interactive simulators */
.pm-result { font-weight: 700; border-radius: 8px; padding: .55rem .8rem; margin-top: .4rem; border: 1px solid var(--border); }
.pm-result.ok   { background: var(--ok-soft);   border-color: var(--ok);   color: var(--ok); }
.pm-result.bad  { background: var(--bad-soft);  border-color: var(--bad);  color: var(--bad); }
.pm-result.warn { background: var(--warn-soft); border-color: var(--warn); color: var(--warn); }
.pm-result.wait { background: var(--info-soft); border-color: var(--info); color: var(--info); }
.pm-trace { margin: .7rem 0 0; font-size: 14.5px; color: var(--muted); }
.demo label.muted { opacity: .5; }

.precedence { list-style: none; padding: 0; counter-reset: p; }
.precedence li {
  counter-increment: p; display: flex; gap: 12px; align-items: flex-start;
  background: var(--surface); border: 1px solid var(--border); border-radius: 8px; padding: .55rem .8rem; margin: .4rem 0;
}
.precedence li::before {
  content: counter(p); flex: none; width: 24px; height: 24px; border-radius: 50%;
  background: var(--accent); color: #fff; font-size: 12px; font-weight: 700; display: grid; place-items: center;
}

kbd {
  font: 12px var(--mono); border: 1px solid var(--border); border-bottom-width: 2px;
  background: var(--surface); border-radius: 5px; padding: 1px 6px; white-space: nowrap;
}

/* Token chips (e.g. tokenizer output) */
.toks { display: flex; flex-wrap: wrap; gap: 6px; margin: 0 0 1.2rem; }
.tok {
  display: inline-flex; flex-direction: column; align-items: center; gap: 2px;
  font: 13.5px var(--mono); background: var(--accent-soft); border: 1px solid var(--accent);
  border-radius: 6px; padding: 4px 8px; white-space: pre;
}
.tok small { font: 11px var(--mono); color: var(--muted); }
.tok:nth-child(3n+2) { background: var(--info-soft); border-color: var(--info); }
.tok:nth-child(3n+3) { background: var(--ok-soft); border-color: var(--ok); }

/* Numbered journey steps */
.steps { list-style: none; padding: 0; margin: 0 0 1.2rem; counter-reset: s; display: grid; gap: 8px; }
.steps li {
  counter-increment: s; display: grid; grid-template-columns: 30px 1fr; gap: 12px; align-items: start;
  background: var(--surface); border: 1px solid var(--border); border-radius: 10px; padding: .7rem .9rem; margin: 0;
}
.steps li::before {
  content: counter(s); width: 28px; height: 28px; border-radius: 50%; background: var(--accent); color: #fff;
  font-weight: 700; font-size: 13px; display: grid; place-items: center;
}
.steps li b { display: block; }
.steps li span { color: var(--muted); font-size: 14.5px; }

/* Probability bars (sampling demo) */
.demo { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 1rem 1.1rem; margin: 0 0 1.2rem; }
.demo .controls { display: flex; flex-wrap: wrap; gap: 16px 28px; align-items: center; margin-bottom: 1rem; font-size: 14px; }
.demo label { display: flex; align-items: center; gap: 8px; }
.demo input[type=range] { accent-color: var(--accent); width: 150px; }
.demo output { font: 13px var(--mono); min-width: 2.5em; }
.bar-row { display: grid; grid-template-columns: 110px 1fr 56px; gap: 10px; align-items: center; font-size: 13.5px; margin: 4px 0; }
.bar-row .lbl { font-family: var(--mono); white-space: pre; overflow: hidden; text-overflow: ellipsis; }
.bar-track { height: 14px; background: var(--surface-2); border-radius: 4px; overflow: hidden; }
.bar-fill { height: 100%; background: var(--accent); border-radius: 4px; transition: width .2s; }
.bar-row.cut { opacity: .35; }
.bar-row.cut .bar-fill { background: var(--muted); }
.bar-row .pct { font: 12.5px var(--mono); text-align: right; color: var(--muted); }
.demo .sample-out { margin-top: .8rem; font-size: 14.5px; }
.btn {
  font: 600 14px var(--font); background: var(--accent); color: #fff; border: 0; border-radius: 8px;
  padding: .45rem .9rem; cursor: pointer;
}

/* Quiz */
.quiz { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 1rem 1.1rem; margin: 0 0 1rem; }
.quiz .q { font-weight: 600; margin-bottom: .6rem; }
.quiz .opts { display: grid; gap: 6px; }
.quiz button.opt {
  text-align: left; font: 14.5px var(--font); color: var(--text); background: var(--surface-2);
  border: 1px solid var(--border); border-radius: 8px; padding: .5rem .75rem; cursor: pointer;
}
.quiz button.opt:hover:not(:disabled) { border-color: var(--accent); }
.quiz button.opt.right { background: var(--ok-soft); border-color: var(--ok); }
.quiz button.opt.wrong { background: var(--bad-soft); border-color: var(--bad); }
.quiz button.opt:disabled { cursor: default; }
.quiz .why { display: none; margin-top: .7rem; font-size: 14.5px; color: var(--muted); }
.quiz.answered .why { display: block; }
.quiz-score { font-weight: 700; color: var(--accent); }

.section-done { display: inline-flex; align-items: center; gap: 6px; font-size: 13px; color: var(--muted); cursor: pointer; user-select: none; margin: -.4rem 0 1rem; }
.section-done input { accent-color: var(--ok); }

.pager { display: flex; justify-content: space-between; gap: 12px; margin-top: 3rem; padding-top: 1.5rem; border-top: 1px solid var(--border); }
footer.site { color: var(--muted); font-size: 13px; margin-top: 2rem; }

/* ---------- Responsive ---------- */
@media (max-width: 1200px) {
  .layout { grid-template-columns: var(--sidebar-w) minmax(0, 1fr); }
  .toc { display: none; }
}
@media (max-width: 860px) {
  .menu-btn { display: inline-block; }
  .layout { grid-template-columns: minmax(0, 1fr); }
  .sidebar {
    position: fixed; left: 0; top: 60px; z-index: 25; width: min(86vw, 320px);
    background: var(--bg); transform: translateX(-102%); transition: transform .2s; box-shadow: 0 10px 30px rgba(0,0,0,.15);
  }
  body.nav-open .sidebar { transform: none; }
  main { padding: 24px 16px 64px; }
  h1 { font-size: 1.7rem; }
  h2 { font-size: 1.35rem; }
}