/* ============================================================
   High Performance AI Lab — book theme
   Matches the lab website: paper #faf9f7, ink #1c1917, oxide
   #c2410c primary, teal #0f766e / cobalt #2563eb secondaries;
   Inter body, IBM Plex Sans display, JetBrains Mono code.
   Light-only, like the site.
   ============================================================ */

/* Self-hosted variable fonts — the same faces the lab website uses.
   Files live in src/hpal-fonts/ (copied unhashed to the book root);
   paths are relative to this stylesheet's location in theme/. */
@font-face {
  font-family: "Inter Variable";
  font-style: normal; font-weight: 100 900; font-display: swap;
  src: url("../hpal-fonts/inter-latin-wght-normal.woff2") format("woff2-variations");
}
@font-face {
  font-family: "IBM Plex Sans Variable";
  font-style: normal; font-weight: 100 900; font-display: swap;
  src: url("../hpal-fonts/ibm-plex-sans-latin-wght-normal.woff2") format("woff2-variations");
}
@font-face {
  font-family: "JetBrains Mono Variable";
  font-style: normal; font-weight: 100 800; font-display: swap;
  src: url("../hpal-fonts/jetbrains-mono-latin-wght-normal.woff2") format("woff2-variations");
}

:root {
  --hpal-paper: #faf9f7;
  --hpal-paper-2: #f5f4f1;
  --hpal-ink: #1c1917;
  --hpal-muted: #57534e;
  --hpal-line: rgba(28, 25, 23, 0.12);
  --hpal-oxide: #c2410c;
  --hpal-oxide-deep: #9a3412;
  --hpal-teal: #0f766e;
  --hpal-cobalt: #2563eb;
}

/* mdBook theme variables, overridden for every theme class so the book
   is brand-light regardless of a stored theme preference */
:root, html.light, html.rust, html.coal, html.navy, html.ayu {
  --bg: var(--hpal-paper);
  --fg: var(--hpal-ink);
  --sidebar-bg: var(--hpal-paper-2);
  --sidebar-fg: var(--hpal-muted);
  --sidebar-non-existant: #c9c5c0;
  --sidebar-active: var(--hpal-oxide);
  --sidebar-spacer: var(--hpal-line);
  --scrollbar: #c9c5c0;
  --icons: var(--hpal-muted);
  --icons-hover: var(--hpal-oxide);
  --links: var(--hpal-oxide);
  --inline-code-color: var(--hpal-teal);
  --theme-popup-bg: #ffffff;
  --theme-popup-border: var(--hpal-line);
  --theme-hover: var(--hpal-paper-2);
  --quote-bg: var(--hpal-paper-2);
  --quote-border: var(--hpal-line);
  --table-border-color: var(--hpal-line);
  --table-header-bg: var(--hpal-paper-2);
  --table-alternate-bg: #fdfcfb;
  --searchbar-border-color: var(--hpal-line);
  --searchbar-bg: #ffffff;
  --searchbar-fg: var(--hpal-ink);
  --searchbar-shadow-color: rgba(28, 25, 23, 0.08);
  --searchresults-header-fg: var(--hpal-muted);
  --searchresults-border-color: var(--hpal-line);
  --searchresults-li-bg: #ffffff;
  --search-mark-bg: #fde5d8;
  --color-scheme: light;
  --footnote-highlight: #fde5d8;
}

/* Typography: same stacks as the website */
html, body {
  font-family: "Inter Variable", "Inter", system-ui, -apple-system, sans-serif;
}
h1, h2, h3, h4, h5, .menu-title {
  font-family: "IBM Plex Sans Variable", "IBM Plex Sans", "Inter Variable", sans-serif;
  font-weight: 700;
  letter-spacing: -0.02em;
}
code, pre, kbd, .sidebar .part-title {
  font-family: "JetBrains Mono Variable", "JetBrains Mono", "SFMono-Regular", Consolas, monospace;
}

/* Chrome: hairlines instead of shadows, paper surfaces */
#menu-bar {
  background: var(--hpal-paper);
  border-bottom: 1px solid var(--hpal-line);
  box-shadow: none;
}
#menu-bar.bordered { border-bottom-color: var(--hpal-line); }
.menu-title { color: var(--hpal-ink); font-size: 1.55rem; }

/* The lab mark next to the book title */
.menu-title::before {
  content: "";
  display: inline-block;
  width: 0.95em;
  height: 0.95em;
  margin-right: 0.45em;
  vertical-align: -0.12em;
  background-image: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 42 42"><g fill="%23e4e1dc"><rect x="0" y="0" width="9" height="9" rx="2"/><rect x="0" y="11" width="9" height="9" rx="2"/><rect x="0" y="22" width="9" height="9" rx="2"/><rect x="11" y="0" width="9" height="9" rx="2"/><rect x="22" y="0" width="9" height="9" rx="2"/><rect x="22" y="11" width="9" height="9" rx="2"/></g><rect x="0" y="33" width="9" height="9" rx="2" fill="%230f766e"/><rect x="11" y="33" width="9" height="9" rx="2" fill="%23137383"/><rect x="11" y="22" width="9" height="9" rx="2" fill="%23167098"/><rect x="11" y="11" width="9" height="9" rx="2" fill="%231a6cac"/><rect x="22" y="33" width="9" height="9" rx="2" fill="%23167098"/><rect x="22" y="22" width="9" height="9" rx="2" fill="%231a6cac"/><rect x="33" y="33" width="9" height="9" rx="2" fill="%231a6cac"/><rect x="33" y="22" width="9" height="9" rx="2" fill="%231e69c1"/><rect x="33" y="11" width="9" height="9" rx="2" fill="%232166d6"/><rect x="33" y="0" width="9" height="9" rx="2" fill="%23c2410c"/></svg>');
  background-size: contain;
  background-repeat: no-repeat;
}

/* Light-only: hide the theme picker (the site commits to one look) */
#mdbook-theme-toggle, #theme-toggle { display: none; }

/* Content rhythm */
.content { line-height: 1.65; }
.content a { color: var(--hpal-oxide); text-decoration: none; }
.content a:hover { color: var(--hpal-oxide-deep); text-decoration: underline; text-underline-offset: 3px; }
.content h1, .content h2 { border-bottom: 1px solid var(--hpal-line); padding-bottom: 0.3em; }
.content blockquote {
  border-left: 3px solid var(--hpal-oxide);
  border-top: 0; border-right: 0; border-bottom: 0;
  background: var(--hpal-paper-2);
}
.content pre {
  border: 1px solid var(--hpal-line);
  border-radius: 6px;
}
.content :not(pre) > code {
  background: var(--hpal-paper-2);
  border-radius: 4px;
  padding: 0.1em 0.35em;
}
.content table { border-collapse: collapse; }
.content table th {
  font-family: "JetBrains Mono Variable", monospace;
  font-size: 0.78em;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--hpal-muted);
}

/* Sidebar: mono part titles, oxide active chapter */
.sidebar { font-size: 0.86em; }
.sidebar .part-title {
  font-size: 0.72em;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--hpal-muted);
}
.chapter li.chapter-item a.active { color: var(--hpal-oxide); font-weight: 600; }

/* Navigation arrows */
.nav-chapters:hover, .mobile-nav-chapters:hover { color: var(--hpal-oxide); }