/* ==========================================================================
   SITG Reference Library
   Cyber, Risk, Governance, Resilience, Transformation, Cryptography & Quantum
   Production stylesheet. GitHub Pages compatible. Iframe embeddable.
   ========================================================================== */

:root {
  --bg: #ffffff;
  --bg-alt: #f5f7fa;
  --bg-elev: #ffffff;
  --surface: #ffffff;
  --border: #e2e8f0;
  --border-strong: #cbd5e1;
  --text: #0f172a;
  --text-soft: #475569;
  --text-mute: #64748b;
  --accent: #0b5cad;
  --accent-soft: #e6f0fa;
  --accent-strong: #084a8c;
  --mark: #fff3bf;
  --mark-text: #5c4400;
  --chip-bg: #eef2f7;
  --chip-text: #334155;
  --shadow: 0 1px 2px rgba(15, 23, 42, .06), 0 4px 12px rgba(15, 23, 42, .05);
  --radius: 10px;
  --radius-sm: 7px;
  --maxw: 1180px;
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

[data-theme="dark"] {
  --bg: #0d1117;
  --bg-alt: #131a23;
  --bg-elev: #161c26;
  --surface: #161c26;
  --border: #232c38;
  --border-strong: #313c4b;
  --text: #e6edf3;
  --text-soft: #aeb9c6;
  --text-mute: #8a96a5;
  --accent: #4ea1f0;
  --accent-soft: #15293f;
  --accent-strong: #6fb4f5;
  --mark: #4a3d00;
  --mark-text: #ffe680;
  --chip-bg: #1c2430;
  --chip-text: #c2cdda;
  --shadow: 0 1px 2px rgba(0, 0, 0, .4), 0 6px 18px rgba(0, 0, 0, .35);
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.55;
  color: var(--text);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

.wrap { max-width: var(--maxw); margin: 0 auto; padding: 0 18px; }

/* ---------- Header ---------- */
.site-header {
  padding: 26px 0 14px;
  border-bottom: 1px solid var(--border);
}
.site-header h1 {
  margin: 0 0 6px;
  font-size: 1.5rem;
  line-height: 1.25;
  letter-spacing: -0.01em;
}
.site-header p.lede {
  margin: 0;
  color: var(--text-soft);
  font-size: 0.95rem;
  max-width: 70ch;
}
.header-row {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 16px;
}
.theme-toggle {
  flex: 0 0 auto;
  border: 1px solid var(--border-strong);
  background: var(--surface);
  color: var(--text-soft);
  border-radius: var(--radius-sm);
  padding: 8px 12px;
  font-size: 0.85rem;
  cursor: pointer;
  white-space: nowrap;
  transition: background .15s, color .15s, border-color .15s;
}
.theme-toggle:hover { border-color: var(--accent); color: var(--accent); }
.theme-toggle:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

/* ---------- Sticky control bar ---------- */
.controls {
  position: sticky;
  top: 0;
  z-index: 50;
  background: color-mix(in srgb, var(--bg) 92%, transparent);
  backdrop-filter: saturate(140%) blur(8px);
  border-bottom: 1px solid var(--border);
  padding: 12px 0 10px;
}
.search-wrap { position: relative; display: flex; align-items: center; }
.search-icon {
  position: absolute; left: 14px;
  width: 18px; height: 18px;
  color: var(--text-mute); pointer-events: none;
}
#search {
  width: 100%;
  padding: 13px 44px 13px 42px;
  font-size: 1rem;
  color: var(--text);
  background: var(--surface);
  border: 1.5px solid var(--border-strong);
  border-radius: var(--radius);
  transition: border-color .15s, box-shadow .15s;
}
#search::placeholder { color: var(--text-mute); }
#search:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-soft);
}
.search-clear {
  position: absolute; right: 8px;
  border: none; background: transparent;
  color: var(--text-mute); cursor: pointer;
  font-size: 1.3rem; line-height: 1;
  padding: 6px 10px; border-radius: var(--radius-sm);
  display: none;
}
.search-clear:hover { color: var(--text); background: var(--bg-alt); }
.search-wrap.has-value .search-clear { display: block; }

/* ---------- Category filters ---------- */
.filters {
  display: flex;
  flex-wrap: wrap;
  gap: 7px;
  margin-top: 10px;
}
.filter-chip {
  border: 1px solid var(--border-strong);
  background: var(--chip-bg);
  color: var(--chip-text);
  border-radius: 999px;
  padding: 5px 12px;
  font-size: 0.8rem;
  cursor: pointer;
  transition: background .12s, color .12s, border-color .12s;
  white-space: nowrap;
}
.filter-chip:hover { border-color: var(--accent); }
.filter-chip[aria-pressed="true"] {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
}
[data-theme="dark"] .filter-chip[aria-pressed="true"] { color: #0d1117; }
.filter-chip:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

/* ---------- Meta row ---------- */
.meta-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  flex-wrap: wrap;
  margin: 14px 0 4px;
}
#result-count { font-size: 0.88rem; color: var(--text-mute); }
#result-count strong { color: var(--text); }

/* ---------- A-Z navigation ---------- */
.az-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 3px;
}
.az-nav a {
  display: inline-flex;
  align-items: center; justify-content: center;
  min-width: 28px; height: 28px;
  padding: 0 4px;
  font-size: 0.82rem; font-weight: 600;
  color: var(--accent);
  text-decoration: none;
  border-radius: var(--radius-sm);
  transition: background .12s, color .12s;
}
.az-nav a:hover { background: var(--accent-soft); }
.az-nav a.disabled {
  color: var(--text-mute);
  opacity: 0.4;
  pointer-events: none;
}

/* ---------- Results ---------- */
main { padding: 4px 0 80px; }
.letter-group { margin-top: 26px; scroll-margin-top: 150px; }
.letter-heading {
  margin: 0 0 6px;
  font-size: 1.15rem;
  color: var(--accent);
  border-bottom: 2px solid var(--border);
  padding-bottom: 4px;
}
.term {
  padding: 11px 2px;
  border-bottom: 1px solid var(--border);
  display: grid;
  grid-template-columns: minmax(180px, 280px) 1fr;
  gap: 6px 22px;
  align-items: baseline;
}
.term-name {
  font-weight: 650;
  color: var(--text);
  letter-spacing: -0.005em;
}
.term-def { color: var(--text-soft); font-size: 0.95rem; }
.term-cat {
  display: inline-block;
  margin-left: 8px;
  font-size: 0.68rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--accent);
  background: var(--accent-soft);
  padding: 1px 7px;
  border-radius: 999px;
  vertical-align: middle;
}
mark {
  background: var(--mark);
  color: var(--mark-text);
  padding: 0 1px;
  border-radius: 2px;
}

/* ---------- Empty state ---------- */
.empty {
  text-align: center;
  padding: 60px 20px;
  color: var(--text-mute);
}
.empty strong { color: var(--text); display: block; margin-bottom: 4px; font-size: 1.05rem; }
.empty .suggest { color: var(--accent); cursor: pointer; text-decoration: underline; }

/* ---------- Back to top ---------- */
#to-top {
  position: fixed;
  right: 20px; bottom: 20px;
  width: 44px; height: 44px;
  border: 1px solid var(--border-strong);
  background: var(--surface);
  color: var(--accent);
  border-radius: 50%;
  cursor: pointer;
  box-shadow: var(--shadow);
  display: flex; align-items: center; justify-content: center;
  opacity: 0; visibility: hidden; transform: translateY(8px);
  transition: opacity .2s, transform .2s, visibility .2s;
  z-index: 60;
}
#to-top.show { opacity: 1; visibility: visible; transform: translateY(0); }
#to-top:hover { border-color: var(--accent); background: var(--accent-soft); }
#to-top:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

/* ---------- Footer ---------- */
.site-footer {
  border-top: 1px solid var(--border);
  padding: 20px 0 40px;
  color: var(--text-mute);
  font-size: 0.82rem;
}
.site-footer a { color: var(--accent); text-decoration: none; }
.site-footer a:hover { text-decoration: underline; }

/* ---------- Loading ---------- */
.loading { padding: 40px 0; color: var(--text-mute); text-align: center; }

/* ---------- Responsive ---------- */
@media (max-width: 760px) {
  body { font-size: 15px; }
  .site-header h1 { font-size: 1.2rem; }
  .term {
    grid-template-columns: 1fr;
    gap: 3px;
  }
  .term-name { font-size: 1rem; }
  .controls { padding-top: 10px; }
  .letter-group { scroll-margin-top: 180px; }
}

@media (max-width: 480px) {
  .az-nav a { min-width: 24px; height: 24px; font-size: 0.75rem; }
  .theme-toggle { padding: 7px 9px; font-size: 0.78rem; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  * { transition: none !important; }
}