/* ── Fixed Income Model Zoo — Base Theme ─────────────────── */

/* ── Dark theme (default) ── */
:root,
[data-theme="dark"] {
  --bg-primary:       #0d1117;
  --bg-secondary:     #161b22;
  --bg-card:          #1c2128;
  --bg-card-hover:    #22272e;
  --bg-input:         #161b22;
  --text-primary:     #e6edf3;
  --text-secondary:   #8b949e;
  --text-muted:       #656d76;
  --text-link:        #58a6ff;
  --border-default:   #30363d;
  --border-muted:     #21262d;
  --shadow-sm:        0 1px 2px rgba(0,0,0,.4);
  --shadow-md:        0 3px 8px rgba(0,0,0,.5);
  --shadow-lg:        0 8px 24px rgba(0,0,0,.6);

  /* Family colors */
  --family-yield-curve:   #58a6ff;
  --family-rate-dynamics: #f0883e;
  --family-forward-rates: #a371f7;
  --family-volatility:    #f85149;
  --family-credit-risk:   #3fb950;
  --family-mortgage:      #d2a8ff;
  --family-inflation:     #e3b341;

  /* Subcategory colors */
  --sub-yc-construction: #58a6ff;
  --sub-yc-parametric:   #79c0ff;
  --sub-rd-equilibrium:  #f0883e;
  --sub-rd-calibrated:   #d29922;
  --sub-fr-general:      #a371f7;
  --sub-fr-market:       #bc8cff;
  --sub-vol-lognormal:   #f85149;
  --sub-vol-stochastic:  #ff7b72;
  --sub-cr-structural:   #3fb950;
  --sub-cr-reduced:      #56d364;
  --sub-mtg-prepayment:  #d2a8ff;
  --sub-mtg-spread:      #e2cbff;
  --sub-inf-nominal:     #e3b341;
  --sub-inf-market:      #f0d060;

  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --transition: .2s ease;
  --max-width: 1400px;
}

/* ── Light theme ── */
[data-theme="light"] {
  --bg-primary:       #ffffff;
  --bg-secondary:     #f6f8fa;
  --bg-card:          #ffffff;
  --bg-card-hover:    #f6f8fa;
  --bg-input:         #f6f8fa;
  --text-primary:     #1f2328;
  --text-secondary:   #656d76;
  --text-muted:       #8b949e;
  --text-link:        #0969da;
  --border-default:   #d0d7de;
  --border-muted:     #e8e8e8;
  --shadow-sm:        0 1px 2px rgba(0,0,0,.06);
  --shadow-md:        0 3px 8px rgba(0,0,0,.1);
  --shadow-lg:        0 8px 24px rgba(0,0,0,.15);
}

/* ── Reset ── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif;
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--text-link); text-decoration: none; }
a:hover { text-decoration: underline; }

/* ── Header ── */
.zoo-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 16px 24px;
  border-bottom: 1px solid var(--border-muted);
}

.zoo-header-left {
  display: flex;
  align-items: center;
  gap: 12px;
}

.zoo-logo {
  width: 36px;
  height: 36px;
}

.zoo-title {
  font-size: 20px;
  font-weight: 700;
  color: var(--text-primary);
}

.zoo-subtitle {
  font-size: 12px;
  color: var(--text-muted);
  font-weight: 400;
  display: block;
}

.zoo-header-actions {
  display: flex;
  align-items: center;
  gap: 8px;
}

.zoo-header-actions a {
  color: var(--text-secondary);
  transition: color var(--transition);
}
.zoo-header-actions a:hover { color: var(--text-primary); }

/* ── Theme Toggle ── */
.theme-toggle {
  background: none;
  border: 1px solid var(--border-default);
  border-radius: var(--radius-sm);
  padding: 6px 8px;
  cursor: pointer;
  color: var(--text-secondary);
  transition: all var(--transition);
  display: flex;
  align-items: center;
}
.theme-toggle:hover {
  color: var(--text-primary);
  border-color: var(--text-muted);
}
.theme-toggle svg { width: 16px; height: 16px; fill: currentColor; }

/* ── Hero ── */
.zoo-hero {
  text-align: center;
  max-width: 720px;
  margin: 48px auto 32px;
  padding: 0 24px;
}

.zoo-hero h1 {
  font-size: 32px;
  font-weight: 800;
  margin-bottom: 12px;
  background: linear-gradient(135deg, var(--family-yield-curve), var(--family-volatility), var(--family-inflation));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.zoo-hero p {
  color: var(--text-secondary);
  font-size: 16px;
  line-height: 1.6;
}

/* ── Section Headers (grouped view) ── */
.family-header {
  font-size: 22px;
  font-weight: 700;
  margin: 40px 0 8px;
  padding-bottom: 8px;
  border-bottom: 2px solid var(--border-muted);
}

.subcategory-header {
  font-size: 15px;
  font-weight: 600;
  color: var(--text-secondary);
  margin: 24px 0 12px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.subcategory-header .dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  display: inline-block;
}

.subcategory-count {
  font-size: 12px;
  color: var(--text-muted);
  font-weight: 400;
}

/* ── Footer ── */
.zoo-footer {
  text-align: center;
  padding: 40px 24px;
  color: var(--text-muted);
  font-size: 13px;
  border-top: 1px solid var(--border-muted);
  margin-top: 60px;
}

/* ── Responsive ── */
@media (max-width: 768px) {
  .zoo-header { padding: 12px 16px; }
  .zoo-hero { margin: 32px auto 24px; }
  .zoo-hero h1 { font-size: 24px; }
  .zoo-hero p { font-size: 14px; }
}