/* ════════════════════════════════════════════════════════════════
   Big O from Scratch · Tutorial-specific styles
   Builds on tutorial.css design tokens.
   ════════════════════════════════════════════════════════════════ */

/* ── Timeline used in §2 (history) ─────────────────────────────── */
.bigo-timeline {
  margin: 1.75rem 0 2.25rem;
  border-left: 1px solid var(--tut-border);
  padding-left: 1.25rem;
}

.bigo-timeline-row {
  display: grid;
  grid-template-columns: 80px 1fr;
  gap: 1.25rem;
  padding: 0.55rem 0;
  align-items: baseline;
}

.bigo-timeline-year {
  font-family: var(--mono);
  font-size: 0.78rem;
  color: var(--tut-accent);
  font-weight: 600;
  letter-spacing: 0.04em;
  position: relative;
}

.bigo-timeline-year::before {
  content: '';
  position: absolute;
  left: -1.95rem;
  top: 0.4em;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--tut-accent);
  box-shadow: 0 0 0 3px rgba(167, 139, 250, 0.15);
}

.bigo-timeline-body {
  font-size: 0.97rem;
  line-height: 1.65;
  color: var(--tut-soft);
}

.bigo-timeline-body strong { color: var(--tut-text); font-weight: 600; }

/* ── Comparison tables used across §4, §5, §8, §9, §14, §15 ───── */
.bigo-table-wrap { overflow-x: auto; margin: 1.5rem 0; }

.bigo-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9rem;
  font-family: var(--mono);
}

.bigo-table th,
.bigo-table td {
  padding: 0.5rem 0.75rem;
  border-bottom: 1px solid var(--tut-border-soft);
  text-align: left;
  vertical-align: top;
  color: var(--tut-soft);
}

.bigo-table thead th {
  font-size: 0.72rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--tut-muted);
  font-weight: 700;
  background: rgba(167, 139, 250, 0.04);
  border-bottom-color: var(--tut-border);
}

.bigo-table tbody tr:hover { background: rgba(167, 139, 250, 0.03); }

.bigo-table td.num {
  font-variant-numeric: tabular-nums;
  color: var(--tut-text);
}
.bigo-table td em { font-style: italic; color: var(--tut-text); }

/* ── Card visual on the home index for this tutorial ───────────── */
.tut-card-visual.bigo-bg {
  background:
    radial-gradient(circle at 25% 30%, rgba(248, 113, 113, 0.22), transparent 45%),
    radial-gradient(circle at 75% 65%, rgba(167, 139, 250, 0.30), transparent 45%),
    linear-gradient(135deg, #1a0a14 0%, #0a0a1f 60%, #0c0f22 100%);
}

/* If the global game-card visual hook is used instead, mirror the gradient */
.game-card-visual.bigo-bg {
  background:
    radial-gradient(circle at 25% 30%, rgba(248, 113, 113, 0.22), transparent 45%),
    radial-gradient(circle at 75% 65%, rgba(167, 139, 250, 0.30), transparent 45%),
    linear-gradient(135deg, #1a0a14 0%, #0a0a1f 60%, #0c0f22 100%);
}