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

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

/* ── Design tokens ─────────────────────────────────────────── */
:root {
  --ferra-ink:        #111009;
  --ferra-ink-soft:   #26201a;
  --ferra-ink-mute:   #6b5f55;
  --ferra-cream:      #f4ede0;
  --ferra-cream-deep: #e8dec9;
  --ferra-rule:       #e2dbd0;
  --ferra-rule-soft:  #ede8e0;
  --ferra-ember:      #c8410b;
  --ferra-ember-dim:  rgba(200,65,11,0.08);
  --ferra-amber:      #f6c016;
  --ferra-teal:       #0e7466;
  --ferra-paper:      #ffffff;
}

/* ── mdBook colour overrides (light theme) ─────────────────── */
.light, html {
  --bg:                      var(--ferra-cream);
  --fg:                      var(--ferra-ink-soft);
  --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:         #f7f4ef;
  --table-alternate-bg:      #faf8f5;
  --searchbar-border-color:  var(--ferra-rule);
  --searchbar-bg:            var(--ferra-paper);
  --searchbar-fg:            var(--ferra-ink);
  --searchbar-shadow-color:  rgba(21,16,12,0.06);
  --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: 1.8;
  color: var(--ferra-ink-soft);
}

/* ── Headings ───────────────────────────────────────────────── */
h1, h2, h3, h4, h5, h6 {
  font-family: 'Fira Sans', sans-serif;
  font-weight: 800;
  color: var(--ferra-ink);
  line-height: 1.2;
  letter-spacing: -0.02em;
}

/* mdBook wraps heading text in <a class="header"> which inherits
   link colour — force headings to stay ink-dark */
h1 a.header, h2 a.header, h3 a.header,
h4 a.header, h5 a.header, h6 a.header {
  color: inherit !important;
  text-decoration: none !important;
}

h1 {
  font-size: 38px;
  margin-bottom: 8px;
  margin-top: 0;
  color: var(--ferra-ink);
}

h2 {
  font-size: 26px;
  margin-top: 48px;
  margin-bottom: 12px;
  padding-bottom: 10px;
  border-bottom: 2px solid var(--ferra-ember);
  color: var(--ferra-ink);
}

h3 {
  font-size: 20px;
  margin-top: 36px;
  margin-bottom: 8px;
  color: var(--ferra-ink);
}

h4 {
  font-size: 12px;
  font-weight: 700;
  margin-top: 28px;
  margin-bottom: 6px;
  color: var(--ferra-ink-mute);
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

/* ── Links ──────────────────────────────────────────────────── */
a { color: var(--ferra-ember); }
a:hover { text-decoration: underline; color: #a33008; }

/* ── Paragraphs & lists ─────────────────────────────────────── */
p { margin: 0 0 1.1em; }

ul, ol {
  padding-left: 1.4em;
  margin: 0 0 1.1em;
}

li { margin-bottom: 0.35em; }

/* ── Inline code ────────────────────────────────────────────── */
code {
  font-family: 'Source Code Pro', monospace;
  font-size: 0.86em;
  background: var(--ferra-ember-dim);
  color: #a33008;
  padding: 2px 5px;
  border-radius: 3px;
  border: 1px solid rgba(200,65,11,0.14);
}

/* ── Code blocks ────────────────────────────────────────────── */
pre {
  background: #1a1410 !important;
  border-radius: 6px;
  padding: 20px 24px !important;
  margin: 1.25em 0;
  box-shadow: 0 2px 8px rgba(0,0,0,0.10);
}

pre code {
  font-family: 'Source Code Pro', monospace;
  font-size: 14px;
  line-height: 1.65;
  background: transparent;
  color: #d8cdb8;
  border: none;
  padding: 0;
}

/* ── Blockquotes / callouts ─────────────────────────────────── */
blockquote {
  border-left: 3px solid var(--ferra-ember);
  background: var(--ferra-cream-deep);
  padding: 14px 20px;
  border-radius: 0 4px 4px 0;
  color: var(--ferra-ink-soft);
  margin: 1.25em 0;
  font-size: 15.5px;
}

blockquote p:last-child { margin-bottom: 0; }

/* ── Horizontal rules ───────────────────────────────────────── */
hr {
  border: none;
  border-top: 1px solid var(--ferra-rule);
  margin: 2.5em 0;
}

/* ── Tables ─────────────────────────────────────────────────── */
table {
  border-collapse: collapse;
  font-size: 15px;
  width: 100%;
  margin: 1.25em 0;
  border: 1px solid var(--ferra-rule);
  border-radius: 4px;
  overflow: hidden;
}

table thead th {
  font-family: 'Fira Sans', sans-serif;
  font-weight: 700;
  font-size: 11.5px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ferra-ink-mute);
  background: #f0ece4;
  padding: 10px 16px;
  border-bottom: 1px solid var(--ferra-rule);
  text-align: left;
}

table td {
  padding: 10px 16px;
  border-bottom: 1px solid var(--ferra-rule-soft);
  vertical-align: top;
}

table tbody tr:last-child td { border-bottom: none; }
table tbody tr:nth-child(even) td { background: #faf8f5; }

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

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

.sidebar-title {
  font-family: 'Fira Sans', sans-serif;
  font-weight: 900;
  font-size: 18px;
  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 10px;
}

.sidebar li a {
  font-family: 'Fira Sans', sans-serif;
  font-size: 13.5px;
  font-weight: 500;
  color: rgba(216,205,184,0.75);
  padding: 5px 12px;
  border-radius: 4px;
  transition: background 0.1s, color 0.1s;
  display: block;
}

.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);
}

/* Section headers in sidebar (top-level entries without links) */
.sidebar li > .chapter-item > a[href] {
  font-weight: 600;
  color: rgba(216,205,184,0.9);
}

/* ── 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: 40px 56px 96px;
  max-width: 800px;
}

/* ── Nav arrows ─────────────────────────────────────────────── */
.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: 28px; }
  h2 { font-size: 21px; }
  h3 { font-size: 17px; }
}