/* ============================================================
   Ferra.rs — mdBook custom theme
   Colours: cream / charcoal-ink / ember / amber / teal
   Fonts  : Fira Sans (body), Roboto Slab (headings), Source Code Pro (code)
   ============================================================ */

@import url('https://fonts.googleapis.com/css2?family=Fira+Sans:wght@400;500;600;700;800&family=Roboto+Slab:wght@700;900&family=Source+Code+Pro:wght@400;500;600&display=swap');

/* ── Design tokens ─────────────────────────────────────────── */
:root {
  --ferra-ink:       #15100c;
  --ferra-ink-soft:  #2b231d;
  --ferra-ink-mute:  #5a4f45;
  --ferra-cream:     #f4ede0;
  --ferra-cream-deep:#e8dec9;
  --ferra-rule:      #d9d2c2;
  --ferra-ember:     #c8410b;
  --ferra-amber:     #f6c016;
  --ferra-teal:      #0e7466;
  --ferra-paper:     #ffffff;
}

/* ── mdBook colour overrides (light theme) ─────────────────── */
.light, html {
  --bg:                      var(--ferra-cream);
  --fg:                      var(--ferra-ink);
  --sidebar-bg:              var(--ferra-ink);
  --sidebar-fg:              #d8cdb8;
  --sidebar-non-existant:    #9b8c7a;
  --sidebar-active:          var(--ferra-amber);
  --sidebar-spacer:          rgba(255,255,255,0.12);
  --scrollbar:               var(--ferra-rule);
  --icons:                   var(--ferra-ink-mute);
  --icons-hover:             var(--ferra-ember);
  --links:                   var(--ferra-ember);
  --inline-code-color:       var(--ferra-ember);
  --theme-popup-bg:          var(--ferra-paper);
  --theme-popup-border:      var(--ferra-rule);
  --theme-hover:             var(--ferra-cream-deep);
  --table-border-color:      var(--ferra-rule);
  --table-header-bg:         var(--ferra-cream-deep);
  --table-alternate-bg:      rgba(244,237,224,0.5);
  --searchbar-border-color:  var(--ferra-rule);
  --searchbar-bg:            var(--ferra-paper);
  --searchbar-fg:            var(--ferra-ink);
  --searchbar-shadow-color:  rgba(21,16,12,0.08);
  --searchresults-header-fg: var(--ferra-ink-mute);
  --searchresults-border-color: var(--ferra-rule);
  --searchresults-li-bg:     var(--ferra-paper);
  --search-mark-bg:          var(--ferra-amber);
  --quote-bg:                var(--ferra-cream-deep);
  --quote-border:            var(--ferra-ember);
  --warning-border:          var(--ferra-amber);
  --color-scheme:            light;
}

/* ── Typography ─────────────────────────────────────────────── */
body {
  font-family: 'Fira Sans', system-ui, sans-serif;
  -webkit-font-smoothing: antialiased;
}

.content main {
  font-size: 17px;
  line-height: 1.75;
  color: var(--ferra-ink-soft);
}

h1, h2, h3, h4, h5, h6 {
  font-family: 'Fira Sans', sans-serif;
  font-weight: 800;
  color: var(--ferra-ink);
  line-height: 1.15;
  letter-spacing: -0.02em;
}

h1 { font-size: 2.4rem; margin-bottom: 0.5em; }
h2 { font-size: 1.7rem; margin-top: 2em; }
h3 { font-size: 1.25rem; margin-top: 1.75em; }

/* Ember underline on h2 */
h2 {
  padding-bottom: 10px;
  border-bottom: 3px solid var(--ferra-ember);
}

/* ── Links ──────────────────────────────────────────────────── */
a { color: var(--ferra-ember); }
a:hover { text-decoration: underline; color: var(--ferra-ink); }

/* ── Inline code ────────────────────────────────────────────── */
code {
  font-family: 'Source Code Pro', monospace;
  font-size: 0.88em;
  background: var(--ferra-cream-deep);
  color: var(--ferra-ember);
  padding: 2px 6px;
  border-radius: 3px;
  border: 1px solid var(--ferra-rule);
}

/* ── Code blocks ────────────────────────────────────────────── */
pre {
  background: var(--ferra-ink) !important;
  border-radius: 6px;
  padding: 20px 24px !important;
}

pre code {
  font-family: 'Source Code Pro', monospace;
  font-size: 14px;
  background: transparent;
  color: #d8cdb8;
  border: none;
  padding: 0;
}

/* ── Blockquotes ────────────────────────────────────────────── */
blockquote {
  border-left: 4px solid var(--ferra-ember);
  background: var(--ferra-cream-deep);
  padding: 12px 20px;
  border-radius: 0 4px 4px 0;
  color: var(--ferra-ink-soft);
}

/* ── Tables ─────────────────────────────────────────────────── */
table {
  border-collapse: collapse;
  font-size: 15px;
}

table thead th {
  font-family: 'Fira Sans', sans-serif;
  font-weight: 700;
  font-size: 12px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ferra-ink-mute);
  background: var(--ferra-cream-deep);
  padding: 10px 16px;
}

table td { padding: 10px 16px; }

/* ── Sidebar ────────────────────────────────────────────────── */
.sidebar {
  background: var(--ferra-ink);
  border-right: none;
}

.sidebar .sidebar-scrollbox {
  padding: 16px 0;
}

/* Sidebar brand header */
.sidebar-title {
  font-family: 'Roboto Slab', serif;
  font-weight: 900;
  font-size: 20px;
  letter-spacing: -0.01em;
  padding: 20px 24px 16px;
  color: #fff;
  border-bottom: 1px solid rgba(255,255,255,0.1);
  margin-bottom: 8px;
}

.sidebar-title span { color: var(--ferra-ember); }

.sidebar ol, .sidebar ul {
  padding: 0 12px;
}

.sidebar li a {
  font-family: 'Fira Sans', sans-serif;
  font-size: 14px;
  font-weight: 500;
  color: rgba(216,205,184,0.8);
  padding: 6px 12px;
  border-radius: 4px;
  transition: background 0.12s, color 0.12s;
}

.sidebar li a:hover {
  color: #fff;
  background: rgba(255,255,255,0.07);
  text-decoration: none;
}

.sidebar li.active > a {
  color: var(--ferra-amber);
  font-weight: 700;
  background: rgba(246,192,22,0.1);
}

/* ── Top nav bar ────────────────────────────────────────────── */
.menu-bar {
  background: var(--ferra-paper);
  border-bottom: 1px solid var(--ferra-rule);
}

/* ── Content area ───────────────────────────────────────────── */
.content {
  background: var(--ferra-cream);
}

.content main {
  padding: 32px 48px 80px;
  max-width: 760px;
}

/* ── Nav arrows (prev/next) ─────────────────────────────────── */
.nav-chapters a {
  color: var(--ferra-ember);
  font-weight: 700;
}

/* ── Search ─────────────────────────────────────────────────── */
#searchbar {
  border: 1px solid var(--ferra-rule);
  border-radius: 4px;
  background: var(--ferra-paper);
  color: var(--ferra-ink);
  font-family: 'Fira Sans', sans-serif;
}

/* ── Mobile ─────────────────────────────────────────────────── */
@media (max-width: 700px) {
  .content main { padding: 24px 20px 64px; }
  h1 { font-size: 1.8rem; }
  h2 { font-size: 1.35rem; }
}