/* nexus.css — cosmix.nexus, the specification suite.
   Dark is the native theme; light is a full token swap under
   [data-theme="light"]. Every colour goes through a token so the toggle
   is one attribute flip. */

:root {
  --bg:            #0B0D12;
  --bg-elevated:   #12151D;
  --bg-soft:       #171B25;
  --bg-code:       #0A0C11;
  --rule:          #2A3142;
  --rule-soft:     #1F2432;
  --ink:           #EDE8D3;
  --ink-soft:      #BDB8A6;
  --ink-faint:     #7F7B6F;
  --ink-dim:       #55535A;

  --accent-orange: #FF6B35;
  --accent-red:    #FF4028;
  --accent-blue:   #6BA4FF;
  --accent-cyan:   #3FD8D8;
  --accent-pink:   #F27BC1;
  --accent-violet: #B186F5;
  --accent-amber:  #F5B944;
  --accent-green:  #6EE38B;

  --glow-1: rgba(255,107,53,0.12);
  --glow-2: rgba(107,164,255,0.08);
  --glow-3: rgba(242,123,193,0.06);
  --page-glow-1: rgba(255,107,53,0.04);
  --page-glow-2: rgba(107,164,255,0.03);
  --toc-bg-a: rgba(11,13,18,0.95);
  --toc-bg-b: rgba(11,13,18,0.85);
  --hover-wash: rgba(255,255,255,0.02);
  --pre-inset: rgba(255,255,255,0.015);
  --pre-shadow: rgba(0,0,0,0.4);
  --noise-opacity: 0.5;
  --noise-blend: overlay;
  --boing-opacity: 0.14;

  --font-display:  "Fraunces", "Libre Caslon Text", Georgia, serif;
  --font-body:     "IBM Plex Sans", "Inter Tight", -apple-system, sans-serif;
  --font-mono:     "JetBrains Mono", "IBM Plex Mono", ui-monospace, monospace;

  --content-max:   880px;
  --page-pad:      clamp(1.25rem, 3vw, 2.5rem);
  --topbar-h:      52px;

  --ch-accent:     var(--accent-orange);
  color-scheme: dark;
}

[data-theme="light"] {
  --bg:            #F6F2E8;
  --bg-elevated:   #FFFDF8;
  --bg-soft:       #EEE9DD;
  --bg-code:       #FBF9F3;
  --rule:          #D8D1C0;
  --rule-soft:     #E6E0D2;
  --ink:           #1C1A17;
  --ink-soft:      #4B4740;
  --ink-faint:     #7A7568;
  --ink-dim:       #A8A395;

  --accent-orange: #D4501A;
  --accent-red:    #C92D1C;
  --accent-blue:   #2A5FC2;
  --accent-cyan:   #0E8484;
  --accent-pink:   #BD3A7E;
  --accent-violet: #6C46C4;
  --accent-amber:  #A86A06;
  --accent-green:  #1E8542;

  --glow-1: rgba(212,80,26,0.10);
  --glow-2: rgba(42,95,194,0.07);
  --glow-3: rgba(189,58,126,0.05);
  --page-glow-1: rgba(212,80,26,0.05);
  --page-glow-2: rgba(42,95,194,0.04);
  --toc-bg-a: rgba(246,242,232,0.96);
  --toc-bg-b: rgba(246,242,232,0.88);
  --hover-wash: rgba(0,0,0,0.03);
  --pre-inset: rgba(0,0,0,0.02);
  --pre-shadow: rgba(60,40,20,0.10);
  --noise-opacity: 0.35;
  --noise-blend: multiply;
  --boing-opacity: 0.22;
  color-scheme: light;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; scroll-padding-top: calc(var(--topbar-h) + 1rem); }

body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.65;
  font-feature-settings: "ss01", "ss02", "cv11";
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  background-image:
    radial-gradient(ellipse 80% 60% at 50% 0%, var(--page-glow-1) 0%, transparent 60%),
    radial-gradient(ellipse 60% 80% at 90% 100%, var(--page-glow-2) 0%, transparent 60%),
    linear-gradient(to bottom, var(--bg), var(--bg));
  background-attachment: fixed;
  transition: background-color 200ms, color 200ms;
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 1;
  background-image:
    url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='120' height='120'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='2' seed='3'/%3E%3CfeColorMatrix values='0 0 0 0 0.95  0 0 0 0 0.92  0 0 0 0 0.83  0 0 0 0.03 0'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
  opacity: var(--noise-opacity);
  mix-blend-mode: var(--noise-blend);
}

/* ----- Top bar ----- */

.topbar {
  position: sticky;
  top: 0;
  z-index: 30;
  height: var(--topbar-h);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 0 var(--page-pad);
  border-bottom: 1px solid var(--rule);
  background: linear-gradient(to bottom, var(--toc-bg-a), var(--toc-bg-b));
  backdrop-filter: blur(10px);
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

.tb-brand {
  color: var(--ink);
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.tb-bullet { color: var(--accent-orange); }
.tb-ver { color: var(--ink-faint); letter-spacing: 0.08em; }

.tb-right { display: inline-flex; align-items: center; gap: 0.35rem; }

.tb-nav {
  color: var(--ink-soft);
  text-decoration: none;
  text-transform: none;
  letter-spacing: 0.06em;
  padding: 0.35rem 0.6rem;
  border: 1px solid transparent;
  border-radius: 3px;
  transition: color 120ms, border-color 120ms, background-color 120ms;
  white-space: nowrap;
}
.tb-nav:hover { color: var(--accent-orange); border-color: var(--rule); background: var(--hover-wash); }
.tb-ext { color: var(--ink-faint); }

.theme-toggle {
  margin-left: 0.4rem;
  width: 36px;
  height: 30px;
  border-radius: 3px;
  border: 1px solid var(--rule);
  background: var(--bg-elevated);
  color: var(--ink-soft);
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 1rem;
  line-height: 1;
  transition: color 120ms, border-color 120ms, transform 120ms;
}
.theme-toggle:hover { color: var(--accent-orange); border-color: var(--accent-orange); transform: translateY(-1px); }
.theme-toggle .tt-sun { display: none; }
.theme-toggle .tt-moon { display: inline; }
[data-theme="light"] .theme-toggle .tt-sun { display: inline; }
[data-theme="light"] .theme-toggle .tt-moon { display: none; }

@media (max-width: 600px) {
  .tb-brand { font-size: 0.62rem; }
  .tb-ext { display: none; }
}

/* ----- Layout shell ----- */

.page {
  display: grid;
  grid-template-columns: minmax(240px, 290px) minmax(0, 1fr);
  gap: 0;
  max-width: 1400px;
  margin: 0 auto;
  position: relative;
  z-index: 2;
}

@media (max-width: 900px) {
  .page { grid-template-columns: 1fr; }
  .toc { position: static !important; height: auto !important; max-height: none !important; border-right: none !important; border-bottom: 1px solid var(--rule); }
}

/* ----- Hero (index only) ----- */

.hero {
  grid-column: 1 / -1;
  padding: clamp(3rem, 8vw, 6rem) var(--page-pad) clamp(2rem, 5vw, 4rem);
  border-bottom: 1px solid var(--rule);
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(circle at 20% 40%, var(--glow-1) 0%, transparent 40%),
    radial-gradient(circle at 80% 70%, var(--glow-2) 0%, transparent 40%),
    radial-gradient(circle at 60% 20%, var(--glow-3) 0%, transparent 40%);
  pointer-events: none;
}

.hero-inner { position: relative; max-width: 1200px; margin: 0 auto; }

.hero-eyebrow {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--accent-orange);
  margin-bottom: 1.5rem;
  display: flex;
  align-items: center;
  gap: 0.75rem;
}
.hero-eyebrow::before,
.hero-eyebrow::after {
  content: "";
  flex: 0 0 auto;
  width: 24px;
  height: 1px;
  background: var(--accent-orange);
  opacity: 0.5;
}
.hero-eyebrow::after { flex: 1; max-width: 120px; }

.hero-title {
  font-family: var(--font-display);
  font-weight: 400;
  font-size: clamp(2.8rem, 8vw, 6rem);
  line-height: 0.95;
  letter-spacing: -0.035em;
  margin: 0 0 1.5rem;
  color: var(--ink);
  font-variation-settings: "SOFT" 50, "WONK" 1;
}
.hero-title em {
  font-style: italic;
  color: var(--accent-orange);
  font-variation-settings: "SOFT" 100, "WONK" 1;
}

.hero-subtitle {
  font-family: var(--font-display);
  font-style: italic;
  font-weight: 300;
  font-size: clamp(1.15rem, 2.3vw, 1.55rem);
  line-height: 1.4;
  color: var(--ink-soft);
  max-width: 52ch;
  margin: 0 0 2.5rem;
}

.hero-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 2rem 3rem;
  padding-top: 2rem;
  border-top: 1px solid var(--rule);
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.04em;
}
.hero-meta-item { display: flex; flex-direction: column; gap: 0.25rem; }
.hero-meta-label { color: var(--ink-faint); text-transform: uppercase; letter-spacing: 0.15em; font-size: 0.68rem; }
.hero-meta-value { color: var(--ink); font-size: 0.95rem; }

.hero-boing {
  position: absolute;
  top: 50%;
  right: -40px;
  width: 180px;
  height: 180px;
  transform: translateY(-50%);
  opacity: var(--boing-opacity);
  pointer-events: none;
}
@media (max-width: 780px) { .hero-boing { display: none; } }

/* ----- Chapter grid (index) ----- */

.chapters {
  padding: clamp(2rem, 5vw, 3.5rem) var(--page-pad) clamp(2rem, 5vw, 3rem);
  border-bottom: 1px solid var(--rule);
}
.chapters-head { max-width: var(--content-max); margin-bottom: 1.5rem; }
.chapters-blurb {
  font-family: var(--font-display);
  font-style: italic;
  font-size: 1.05rem;
  line-height: 1.5;
  color: var(--ink-soft);
  margin: 0;
  max-width: 60ch;
}
.chapter-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 0.75rem;
}
.card {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 0.9rem;
  padding: 0.9rem 1rem;
  border: 1px solid var(--rule);
  border-left: 3px solid var(--ch-accent);
  border-radius: 4px;
  background: var(--bg-elevated);
  color: var(--ink);
  text-decoration: none;
  transition: border-color 120ms, transform 120ms, background-color 120ms;
}
.card:hover { border-color: var(--ch-accent); transform: translateY(-1px); background: color-mix(in srgb, var(--ch-accent) 5%, var(--bg-elevated)); }
.card-num {
  font-family: var(--font-display);
  font-size: 1.6rem;
  line-height: 1;
  color: var(--ch-accent);
  font-feature-settings: "lnum", "tnum";
  padding-top: 0.1rem;
  min-width: 2.2rem;
}
.card-body { display: flex; flex-direction: column; gap: 0.35rem; min-width: 0; }
.card-title { font-size: 0.9rem; font-weight: 500; line-height: 1.3; }
.card-title code, .toc-chapter-title code, .chapter-title code {
  font-family: var(--font-mono); font-size: 0.85em; color: var(--ch-accent);
}
.card-meta {
  display: flex;
  justify-content: space-between;
  gap: 0.75rem;
  font-family: var(--font-mono);
  font-size: 0.62rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}
.card-layer { color: var(--ch-accent); opacity: 0.85; }
.card-status { color: var(--ink-faint); }
.card.st-retired { opacity: 0.6; }
.card.st-retired .card-title { text-decoration: line-through; text-decoration-color: var(--ink-dim); }
.card.st-retired:hover { opacity: 0.9; }
.chapters-note {
  margin: 1.25rem 0 0;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.04em;
  color: var(--ink-faint);
  max-width: 70ch;
}

/* ----- TOC ----- */

.toc {
  position: sticky;
  top: var(--topbar-h);
  height: calc(100vh - var(--topbar-h));
  max-height: calc(100vh - var(--topbar-h));
  overflow: hidden;
  border-right: 1px solid var(--rule);
  background: linear-gradient(to bottom, var(--toc-bg-a), var(--toc-bg-b));
  backdrop-filter: blur(10px);
  z-index: 10;
}
.toc-inner { height: 100%; display: flex; flex-direction: column; padding: 1.5rem 0 0; }
.toc-title {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--ink-faint);
  padding: 0 1.5rem 1rem;
  border-bottom: 1px solid var(--rule-soft);
  display: flex;
  align-items: center;
  gap: 0.6rem;
}
.toc-bullet { color: var(--accent-orange); font-size: 0.9rem; }
.toc-scroll {
  flex: 1;
  overflow-y: auto;
  overflow-x: hidden;
  padding: 1rem 0 3rem;
  scrollbar-width: thin;
  scrollbar-color: var(--rule) transparent;
}
.toc-scroll::-webkit-scrollbar { width: 6px; }
.toc-scroll::-webkit-scrollbar-track { background: transparent; }
.toc-scroll::-webkit-scrollbar-thumb { background: var(--rule); border-radius: 3px; }

.toc-back {
  display: block;
  padding: 0.4rem 1.5rem 0.6rem;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--ink-faint);
  text-decoration: none;
}
.toc-back:hover { color: var(--accent-orange); }

.toc-chapter {
  display: flex;
  align-items: flex-start;
  gap: 0.85rem;
  padding: 0.85rem 1.5rem 0.5rem;
  text-decoration: none;
  color: var(--ink);
  position: relative;
  transition: background-color 120ms;
}
.toc-chapter:hover { background: var(--hover-wash); }
.toc-chapter::before {
  content: "";
  position: absolute;
  left: 0;
  top: 1rem;
  bottom: 0.5rem;
  width: 2px;
  background: var(--ch-accent);
  opacity: 0;
  transition: opacity 120ms;
}
.toc-chapter:hover::before,
.toc-chapter.active::before { opacity: 1; }
.toc-num {
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 1.05rem;
  color: var(--ch-accent);
  line-height: 1;
  padding-top: 0.15rem;
  min-width: 1.6rem;
  font-feature-settings: "lnum", "tnum";
}
.toc-chapter-text { display: flex; flex-direction: column; gap: 0.15rem; min-width: 0; flex: 1; }
.toc-chapter-title { font-size: 0.85rem; font-weight: 500; letter-spacing: -0.005em; line-height: 1.3; }
.toc-chapter-badge {
  font-family: var(--font-mono);
  font-size: 0.6rem;
  text-transform: uppercase;
  letter-spacing: 0.2em;
  color: var(--ch-accent);
  opacity: 0.7;
}
.toc-chapter.st-retired .toc-chapter-title { color: var(--ink-faint); }

.toc-sections {
  list-style: none;
  margin: 0.25rem 0 0.75rem;
  padding: 0 1.5rem 0 1.5rem;
}
.toc-sections li { margin: 0; padding: 0; }
.toc-sections a {
  display: block;
  font-size: 0.78rem;
  color: var(--ink-faint);
  text-decoration: none;
  padding: 0.3rem 0 0.3rem 0.6rem;
  line-height: 1.35;
  border-left: 1px solid var(--rule-soft);
  transition: color 120ms, padding-left 120ms, border-color 120ms;
}
.toc-sections a:hover { color: var(--ch-accent); padding-left: 0.9rem; }
.toc-sections a.active { color: var(--ink); border-left-color: var(--ch-accent); }

.toc-neighbours { border-top: 1px solid var(--rule-soft); margin-top: 0.5rem; padding-top: 0.5rem; }
.toc-neighbours .toc-chapter-badge::before { content: "next · "; }
.toc-neighbours .toc-prev .toc-chapter-badge::before { content: "previous · "; }

/* ----- Main content ----- */

main { padding: 0; min-width: 0; }

.chapter {
  padding: clamp(2.5rem, 6vw, 5rem) var(--page-pad) clamp(3rem, 7vw, 6rem);
  border-bottom: 1px solid var(--rule);
  position: relative;
}
.chapter:last-child { border-bottom: none; }

.chapter-header {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: clamp(1.5rem, 3vw, 2.5rem);
  padding-bottom: 2.5rem;
  margin-bottom: 3rem;
  border-bottom: 1px solid var(--rule);
  max-width: var(--content-max);
  align-items: start;
}
@media (max-width: 600px) { .chapter-header { grid-template-columns: 1fr; gap: 1rem; } }

.chapter-numeral {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.3rem;
  padding: 0.75rem 1.1rem 0.85rem;
  border: 1px solid var(--ch-accent);
  border-radius: 3px;
  background: linear-gradient(135deg,
    color-mix(in srgb, var(--ch-accent) 10%, transparent),
    color-mix(in srgb, var(--ch-accent) 2%, transparent));
  position: relative;
}
.chapter-numeral::before {
  content: ""; position: absolute; top: -4px; left: -4px; width: 8px; height: 8px;
  border-top: 1px solid var(--ch-accent); border-left: 1px solid var(--ch-accent);
}
.chapter-numeral::after {
  content: ""; position: absolute; bottom: -4px; right: -4px; width: 8px; height: 8px;
  border-bottom: 1px solid var(--ch-accent); border-right: 1px solid var(--ch-accent);
}
.numeral-digit {
  font-family: var(--font-display);
  font-weight: 400;
  font-size: 2.6rem;
  line-height: 0.85;
  color: var(--ch-accent);
  font-variation-settings: "SOFT" 100, "WONK" 1;
  font-feature-settings: "lnum", "tnum";
}
.numeral-label {
  font-family: var(--font-mono);
  font-size: 0.58rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--ch-accent);
}

.chapter-eyebrow {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--ch-accent);
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  margin-bottom: 1rem;
}
.eyebrow-dot { width: 6px; height: 6px; background: var(--ch-accent); border-radius: 50%; display: inline-block; }

.chapter-title {
  font-family: var(--font-display);
  font-weight: 400;
  font-size: clamp(2rem, 5vw, 3.2rem);
  line-height: 1.02;
  letter-spacing: -0.022em;
  margin: 0 0 1.25rem;
  color: var(--ink);
  font-variation-settings: "SOFT" 40, "WONK" 0;
}

.chapter-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 1.25rem;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.04em;
}
.meta-item { display: inline-flex; align-items: center; gap: 0.45rem; }
.meta-label { text-transform: uppercase; letter-spacing: 0.15em; color: var(--ink-faint); font-size: 0.62rem; }
.meta-val { color: var(--ink-soft); }
.meta-val.status-stable  { color: var(--accent-green); }
.meta-val.status-draft   { color: var(--accent-amber); }
.meta-val.status-retired { color: var(--accent-red); }
.card-status.status-stable  { color: var(--accent-green); }
.card-status.status-retired { color: var(--accent-red); }

.notice {
  max-width: var(--content-max);
  margin: 0 0 2.5rem;
  padding: 0.9rem 1.1rem;
  border: 1px solid var(--rule);
  border-left: 3px solid var(--accent-red);
  border-radius: 3px;
  background: color-mix(in srgb, var(--accent-red) 6%, var(--bg-elevated));
  font-size: 0.92rem;
  color: var(--ink-soft);
}
.notice strong { color: var(--accent-red); }

.chapter-body { max-width: var(--content-max); }

/* ----- Prose ----- */

.prose { font-size: 1rem; line-height: 1.7; color: var(--ink); }
.prose > * { max-width: 100%; }
.prose > *:first-child { margin-top: 0; }

.prose h1 {
  font-family: var(--font-display);
  font-weight: 400;
  font-size: 2rem;
  line-height: 1.15;
  letter-spacing: -0.015em;
  color: var(--ink);
  margin: 3.5rem 0 1rem;
  padding-bottom: 0.5rem;
  border-bottom: 1px dashed var(--rule);
}

.prose .heading-h2 {
  font-family: var(--font-display);
  font-weight: 400;
  font-size: 1.75rem;
  line-height: 1.2;
  letter-spacing: -0.018em;
  color: var(--ink);
  margin: 3.5rem 0 1rem;
  padding-top: 1rem;
  position: relative;
}
.prose .heading-h2::before {
  content: ""; position: absolute; top: 0; left: 0; width: 42px; height: 2px; background: var(--ch-accent);
}

.prose .heading-h3 {
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 1.3rem;
  line-height: 1.3;
  letter-spacing: -0.01em;
  color: var(--ink);
  margin: 2.5rem 0 0.75rem;
}
.prose .heading-h3::before {
  content: "§"; color: var(--ch-accent); opacity: 0.6; margin-right: 0.5rem;
  font-family: var(--font-display); font-style: italic;
}

.prose .heading-h4 {
  font-family: var(--font-body);
  font-weight: 600;
  font-size: 1rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--ch-accent);
  margin: 2rem 0 0.5rem;
}

.prose p { margin: 0 0 1.1rem; color: var(--ink); }

.prose a {
  color: var(--ch-accent);
  text-decoration: none;
  border-bottom: 1px solid color-mix(in srgb, var(--ch-accent) 40%, transparent);
  transition: border-color 120ms, color 120ms;
}
.prose a:hover { border-bottom-color: var(--ch-accent); }
.prose a.dead {
  color: var(--ink-soft);
  border-bottom: 1px dotted var(--ink-dim);
  cursor: help;
}

.prose strong { color: var(--ink); font-weight: 600; }
.prose em { font-style: italic; color: var(--ink); }

.prose ul, .prose ol { margin: 0 0 1.1rem; padding-left: 1.5rem; }
.prose ul li, .prose ol li { margin: 0.3rem 0; }
.prose ul li::marker { color: var(--ch-accent); }
.prose ol li::marker { color: var(--ch-accent); font-family: var(--font-mono); font-size: 0.85em; }
.prose li > p { margin-bottom: 0.4rem; }
.prose input[type="checkbox"] { accent-color: var(--ch-accent); margin-right: 0.4rem; }

.prose blockquote {
  margin: 1.5rem 0;
  padding: 1rem 1.25rem 1rem 1.5rem;
  border-left: 2px solid var(--ch-accent);
  background: linear-gradient(to right, color-mix(in srgb, var(--ch-accent) 6%, transparent), transparent 60%);
  font-family: var(--font-display);
  font-style: italic;
  font-size: 1.05rem;
  line-height: 1.5;
  color: var(--ink);
  border-radius: 0 3px 3px 0;
}
.prose blockquote p { margin: 0.3rem 0; }
.prose blockquote code { font-style: normal; }

.prose hr {
  border: none;
  height: 1px;
  background: linear-gradient(to right, transparent, var(--rule) 20%, var(--rule) 80%, transparent);
  margin: 3rem 0;
  position: relative;
}
.prose hr::after {
  content: "◆";
  position: absolute; top: 50%; left: 50%; transform: translate(-50%, -50%);
  background: var(--bg); padding: 0 0.6rem; color: var(--ch-accent); font-size: 0.7rem; letter-spacing: 0.5em;
}

.prose code {
  font-family: var(--font-mono);
  font-size: 0.88em;
  padding: 0.12em 0.4em;
  background: color-mix(in srgb, var(--ch-accent) 10%, var(--bg-elevated));
  border: 1px solid color-mix(in srgb, var(--ch-accent) 18%, transparent);
  border-radius: 3px;
  color: color-mix(in srgb, var(--ch-accent) 85%, var(--ink));
  white-space: nowrap;
}
.prose pre code {
  background: none; border: none; padding: 0; color: var(--ink);
  white-space: pre; font-size: 0.84em; line-height: 1.55;
}
.prose pre {
  margin: 1.5rem 0;
  padding: 1.15rem 1.25rem;
  background: var(--bg-code);
  border: 1px solid var(--rule);
  border-left: 3px solid var(--ch-accent);
  border-radius: 4px;
  overflow-x: auto;
  position: relative;
  scrollbar-width: thin;
  scrollbar-color: var(--rule) transparent;
  box-shadow: inset 0 0 0 1px var(--pre-inset), 0 1px 2px var(--pre-shadow);
}
.prose pre::before {
  content: ""; position: absolute; top: 0.6rem; right: 0.8rem; width: 6px; height: 6px;
  background: var(--ch-accent); border-radius: 50%; opacity: 0.5;
  box-shadow: 10px 0 0 color-mix(in srgb, var(--ch-accent) 40%, transparent),
              20px 0 0 color-mix(in srgb, var(--ch-accent) 25%, transparent);
}
.prose pre::-webkit-scrollbar { height: 6px; }
.prose pre::-webkit-scrollbar-track { background: transparent; }
.prose pre::-webkit-scrollbar-thumb { background: var(--rule); border-radius: 3px; }

.prose img { max-width: 100%; height: auto; }

.prose .footnote-definition { font-size: 0.9rem; color: var(--ink-soft); }
.prose sup { font-size: 0.7em; }

/* ----- Tables ----- */

.table-wrap {
  margin: 1.75rem 0;
  overflow-x: auto;
  border: 1px solid var(--rule);
  border-radius: 4px;
  background: var(--bg-elevated);
  scrollbar-width: thin;
  scrollbar-color: var(--rule) transparent;
}
.table-wrap::-webkit-scrollbar { height: 8px; }
.table-wrap::-webkit-scrollbar-track { background: transparent; }
.table-wrap::-webkit-scrollbar-thumb { background: var(--rule); border-radius: 4px; }

.prose table { width: 100%; border-collapse: collapse; font-size: 0.9rem; line-height: 1.5; }
.prose thead { background: linear-gradient(to bottom, var(--bg-soft), var(--bg-elevated)); }
.prose th {
  padding: 0.75rem 1rem;
  text-align: left;
  font-weight: 500;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--ch-accent);
  border-bottom: 1px solid var(--ch-accent);
  white-space: nowrap;
}
.prose td { padding: 0.7rem 1rem; border-top: 1px solid var(--rule-soft); color: var(--ink); vertical-align: top; }
.prose tr:hover td { background: color-mix(in srgb, var(--ch-accent) 4%, transparent); }
.prose td code, .prose th code { font-size: 0.85em; padding: 0.05em 0.35em; white-space: nowrap; }

/* ----- Footer ----- */

footer {
  grid-column: 1 / -1;
  padding: 3rem var(--page-pad) 4rem;
  border-top: 1px solid var(--rule);
  text-align: center;
  color: var(--ink-faint);
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.08em;
  background: var(--bg-elevated);
  position: relative;
  z-index: 2;
}
footer a { color: var(--ink-soft); text-decoration: none; border-bottom: 1px solid var(--rule); }
footer a:hover { color: var(--accent-orange); border-bottom-color: var(--accent-orange); }
footer .footer-mark {
  font-family: var(--font-display);
  font-style: italic;
  font-size: 1.15rem;
  color: var(--ink);
  margin-bottom: 0.75rem;
  letter-spacing: -0.01em;
}
footer .footer-rule { width: 60px; height: 1px; background: var(--accent-orange); margin: 0 auto 1.25rem; opacity: 0.6; }

/* ----- Back-to-top ----- */

.to-top {
  position: fixed;
  bottom: 1.5rem;
  right: 1.5rem;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--bg-elevated);
  border: 1px solid var(--rule);
  color: var(--ink-soft);
  display: flex;
  align-items: center;
  justify-content: center;
  text-decoration: none;
  transition: opacity 200ms, transform 120ms, color 120ms, border-color 120ms;
  opacity: 0;
  pointer-events: none;
  z-index: 20;
  font-family: var(--font-mono);
  font-size: 1rem;
}
.to-top.visible { opacity: 0.85; pointer-events: auto; }
.to-top:hover { opacity: 1; color: var(--accent-orange); border-color: var(--accent-orange); transform: translateY(-2px); }

/* ----- Mobile TOC ----- */

@media (max-width: 900px) {
  .toc-scroll { max-height: 0; transition: max-height 300ms; padding: 0; }
  .toc.open .toc-scroll { max-height: 70vh; padding: 1rem 0 3rem; }
  .toc-title { cursor: pointer; user-select: none; }
  .toc-title::after { content: "▾"; margin-left: auto; transition: transform 200ms; }
  .toc.open .toc-title::after { transform: rotate(180deg); }
}

@media (prefers-reduced-motion: reduce) {
  * { animation: none !important; transition: none !important; }
  html { scroll-behavior: auto; }
}