:root {
  --rh-red: #EE0000;
  --rh-red-dark: #C00;
  --rh-bg: #151515;
  --rh-card: #292929;
  --rh-card-border: #3C3F42;
  --rh-text: #E0E0E0;
  --rh-text-muted: #A0A0A0;
  --rh-blue: #0066CC;
  --rh-blue-dark: #004C99;
  --rh-code-bg: #0F3460;
  --rh-sidebar-w: 280px;
  --rh-header-h: 64px;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  font-family: "Red Hat Text", "Red Hat Display", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background: var(--rh-bg);
  color: var(--rh-text);
  line-height: 1.7;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* ── Header ─────────────────────────────────────────────── */
.site-header {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: var(--rh-header-h);
  background: var(--rh-card);
  border-bottom: 2px solid var(--rh-red);
  display: flex;
  align-items: center;
  padding: 0 24px;
  z-index: 1000;
  gap: 16px;
}

.site-header .logo {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  color: #fff;
  font-weight: 700;
  font-size: 1.15rem;
  white-space: nowrap;
}

.site-header .logo .hat {
  width: 36px;
  height: 36px;
  background: var(--rh-red);
  border-radius: 6px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.3rem;
  flex-shrink: 0;
}

.hamburger {
  display: none;
  background: none;
  border: none;
  color: #fff;
  font-size: 1.6rem;
  cursor: pointer;
  padding: 4px 8px;
}

.header-links {
  margin-left: auto;
  display: flex;
  gap: 16px;
  align-items: center;
}

.header-links a {
  color: var(--rh-text-muted);
  text-decoration: none;
  font-size: 0.9rem;
  transition: color 0.2s;
}

.header-links a:hover { color: #fff; }

/* ── Layout ─────────────────────────────────────────────── */
.layout {
  display: flex;
  margin-top: var(--rh-header-h);
  flex: 1;
}

/* ── Sidebar ────────────────────────────────────────────── */
.sidebar {
  position: fixed;
  top: var(--rh-header-h);
  left: 0;
  bottom: 0;
  width: var(--rh-sidebar-w);
  background: var(--rh-card);
  border-right: 1px solid var(--rh-card-border);
  padding: 24px 0;
  overflow-y: auto;
  z-index: 900;
  transition: transform 0.3s ease;
}

.sidebar nav { display: flex; flex-direction: column; }

.sidebar .nav-section {
  padding: 8px 24px 4px;
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 1.5px;
  color: var(--rh-text-muted);
  font-weight: 700;
}

.sidebar a {
  display: block;
  padding: 10px 24px;
  color: var(--rh-text);
  text-decoration: none;
  font-size: 0.95rem;
  border-left: 3px solid transparent;
  transition: all 0.2s;
}

.sidebar a:hover {
  background: rgba(255, 255, 255, 0.05);
  color: #fff;
}

.sidebar a.active {
  border-left-color: var(--rh-red);
  background: rgba(238, 0, 0, 0.08);
  color: #fff;
  font-weight: 600;
}

/* ── Main Content ───────────────────────────────────────── */
.main {
  margin-left: var(--rh-sidebar-w);
  flex: 1;
  padding: 48px 56px 80px;
  max-width: 960px;
  min-width: 0;
}

.main h1 {
  font-size: 2.4rem;
  font-weight: 700;
  color: #fff;
  margin-bottom: 8px;
  line-height: 1.2;
}

.main .subtitle {
  font-size: 1.1rem;
  color: var(--rh-text-muted);
  margin-bottom: 40px;
}

.main h2 {
  font-size: 1.55rem;
  font-weight: 700;
  color: #fff;
  margin-top: 48px;
  margin-bottom: 16px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--rh-card-border);
}

.main h3 {
  font-size: 1.2rem;
  font-weight: 600;
  color: #fff;
  margin-top: 32px;
  margin-bottom: 12px;
}

.main p { margin-bottom: 16px; }

.main ul, .main ol {
  margin-bottom: 16px;
  padding-left: 24px;
}

.main li { margin-bottom: 6px; }

.main a {
  color: var(--rh-blue);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color 0.2s;
}

.main a:hover { border-bottom-color: var(--rh-blue); }

/* ── Cards ──────────────────────────────────────────────── */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 20px;
  margin: 24px 0;
}

.card {
  background: var(--rh-card);
  border: 1px solid var(--rh-card-border);
  border-radius: 12px;
  padding: 28px 24px;
  transition: border-color 0.2s, transform 0.2s;
}

.card:hover {
  border-color: var(--rh-red);
  transform: translateY(-2px);
}

.card h3 {
  margin-top: 0;
  margin-bottom: 8px;
  font-size: 1.1rem;
}

.card p {
  font-size: 0.92rem;
  color: var(--rh-text-muted);
  margin-bottom: 0;
}

.card .icon {
  font-size: 2rem;
  margin-bottom: 12px;
  display: block;
}

/* ── Tables ─────────────────────────────────────────────── */
.table-wrap { overflow-x: auto; margin: 20px 0; }

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.92rem;
}

thead th {
  background: var(--rh-card);
  color: #fff;
  font-weight: 600;
  text-align: left;
  padding: 12px 16px;
  border-bottom: 2px solid var(--rh-red);
  white-space: nowrap;
}

tbody td {
  padding: 10px 16px;
  border-bottom: 1px solid var(--rh-card-border);
  vertical-align: top;
}

tbody tr:hover { background: rgba(255, 255, 255, 0.03); }

/* ── Code blocks ────────────────────────────────────────── */
code {
  font-family: "Red Hat Mono", "JetBrains Mono", "Fira Code", monospace;
  font-size: 0.88em;
}

:not(pre) > code {
  background: var(--rh-code-bg);
  color: var(--rh-red);
  padding: 2px 8px;
  border-radius: 4px;
}

pre {
  background: #0D1117;
  border: 1px solid var(--rh-card-border);
  border-radius: 8px;
  padding: 20px 24px;
  overflow-x: auto;
  margin: 16px 0 24px;
  line-height: 1.5;
}

pre code {
  color: var(--rh-text);
  font-size: 0.85rem;
}

/* ── Badges ─────────────────────────────────────────────── */
.badge {
  display: inline-block;
  padding: 3px 12px;
  border-radius: 12px;
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.3px;
}

.badge-required { background: var(--rh-red); color: #fff; }
.badge-optional { background: var(--rh-blue); color: #fff; }
.badge-core     { background: #4A154B; color: #fff; }

/* ── Alert / Callout ────────────────────────────────────── */
.callout {
  border-left: 4px solid var(--rh-blue);
  background: rgba(0, 102, 204, 0.08);
  padding: 16px 20px;
  border-radius: 0 8px 8px 0;
  margin: 20px 0;
}

.callout.warning {
  border-left-color: #F0AB00;
  background: rgba(240, 171, 0, 0.08);
}

.callout.danger {
  border-left-color: var(--rh-red);
  background: rgba(238, 0, 0, 0.08);
}

.callout strong { color: #fff; }

/* ── Hero ───────────────────────────────────────────────── */
.hero {
  background: linear-gradient(135deg, var(--rh-card) 0%, #1a1a2e 100%);
  border: 1px solid var(--rh-card-border);
  border-radius: 16px;
  padding: 48px 40px;
  margin-bottom: 40px;
  text-align: center;
}

.hero h1 { font-size: 2.6rem; margin-bottom: 16px; }

.hero .subtitle { font-size: 1.15rem; max-width: 680px; margin: 0 auto 28px; }

.btn {
  display: inline-block;
  padding: 12px 32px;
  border-radius: 6px;
  font-weight: 600;
  font-size: 1rem;
  text-decoration: none;
  transition: background 0.2s, transform 0.1s;
}

.btn-primary {
  background: var(--rh-red);
  color: #fff;
}

.btn-primary:hover {
  background: var(--rh-red-dark);
  transform: translateY(-1px);
}

.btn-secondary {
  background: var(--rh-card);
  color: #fff;
  border: 1px solid var(--rh-card-border);
  margin-left: 12px;
}

.btn-secondary:hover {
  border-color: var(--rh-text-muted);
}

/* ── Diagram ────────────────────────────────────────────── */
.diagram {
  background: var(--rh-card);
  border: 1px solid var(--rh-card-border);
  border-radius: 12px;
  padding: 32px;
  margin: 24px 0;
  overflow-x: auto;
  text-align: center;
}

.diagram pre {
  background: transparent;
  border: none;
  display: inline-block;
  text-align: left;
  margin: 0;
  padding: 0;
}

/* ── Steps ──────────────────────────────────────────────── */
.steps { counter-reset: step; list-style: none; padding-left: 0; }

.steps li {
  counter-increment: step;
  padding: 20px 24px 20px 72px;
  position: relative;
  margin-bottom: 16px;
  background: var(--rh-card);
  border: 1px solid var(--rh-card-border);
  border-radius: 10px;
}

.steps li::before {
  content: counter(step);
  position: absolute;
  left: 20px;
  top: 18px;
  width: 36px;
  height: 36px;
  background: var(--rh-red);
  color: #fff;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 1rem;
}

.steps li strong { color: #fff; }

/* ── Footer ─────────────────────────────────────────────── */
.site-footer {
  margin-left: var(--rh-sidebar-w);
  padding: 24px 56px;
  border-top: 1px solid var(--rh-card-border);
  color: var(--rh-text-muted);
  font-size: 0.85rem;
  text-align: center;
}

.site-footer a { color: var(--rh-blue); text-decoration: none; }

/* ── Responsive ─────────────────────────────────────────── */
@media (max-width: 900px) {
  .hamburger { display: block; }

  .sidebar {
    transform: translateX(-100%);
  }

  .sidebar.open {
    transform: translateX(0);
    box-shadow: 4px 0 24px rgba(0,0,0,0.5);
  }

  .main {
    margin-left: 0;
    padding: 32px 20px 60px;
  }

  .site-footer { margin-left: 0; padding: 24px 20px; }

  .hero { padding: 32px 20px; }
  .hero h1 { font-size: 1.8rem; }

  .main h1 { font-size: 1.8rem; }

  .card-grid { grid-template-columns: 1fr; }
}

/* ── Overlay for mobile sidebar ─────────────────────────── */
.sidebar-overlay {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.5);
  z-index: 899;
}

.sidebar-overlay.active { display: block; }

/* ── hljs overrides ─────────────────────────────────────── */
.hljs { background: transparent !important; padding: 0 !important; }