/* ════════════════════════════════════════════════════════════════
   Vertex Animation Textures · Tutorial-specific styles
   Builds on tutorial.css design tokens.
   ════════════════════════════════════════════════════════════════ */

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

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

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

.vat-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);
}

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

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

/* ── Comparison tables shared with file-streaming styles ───────── */
.vat-table-wrap { overflow-x: auto; margin: 1.5rem 0; }

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

.vat-table th,
.vat-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);
}

.vat-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);
}

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

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

/* Bar cell inside a table */
.vat-table td.bar {
  position: relative;
  min-width: 140px;
  background: linear-gradient(180deg, transparent, transparent);
}
.vat-table td.bar .bar-fill {
  display: inline-block;
  height: 8px;
  background: linear-gradient(90deg, var(--tut-accent-2), var(--tut-accent));
  border-radius: 4px;
  vertical-align: middle;
}

/* ── Tutorial card visual on the index ─────────────────────────── */
.tut-card-visual.vat-bg {
  background:
    radial-gradient(circle at 20% 30%, rgba(52, 211, 153, 0.30), transparent 45%),
    radial-gradient(circle at 80% 60%, rgba(167, 139, 250, 0.35), transparent 45%),
    linear-gradient(135deg, #0a1428 0%, #1a0a2e 60%, #0c1f1a 100%);
}

/* ── Per-tutorial card-visual stream-bg referenced from index ──── */
.tut-card-visual.stream-bg {
  background:
    radial-gradient(circle at 25% 30%, rgba(96, 165, 250, 0.30), transparent 45%),
    radial-gradient(circle at 75% 70%, rgba(52, 211, 153, 0.25), transparent 45%),
    linear-gradient(135deg, #0a1428 0%, #0c1f1a 100%);
}

.tut-card-visual.jobs-bg {
  background:
    radial-gradient(circle at 30% 40%, rgba(251, 191, 36, 0.30), transparent 45%),
    radial-gradient(circle at 70% 60%, rgba(167, 139, 250, 0.25), transparent 45%),
    linear-gradient(135deg, #1a0a14 0%, #200a30 50%, #14140a 100%);
}

/* ── Tex-strip: rendering of a small VAT texture inline ────────── */
.tex-strip {
  display: inline-block;
  vertical-align: middle;
  border: 1px solid var(--tut-border);
  border-radius: 4px;
  image-rendering: pixelated;
  image-rendering: crisp-edges;
}

/* ── Mode pills used on the four-modes selector widget ────────── */
.vat-mode-pills {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  font-family: var(--mono);
  font-size: 0.75rem;
}

.vat-mode-pill {
  padding: 0.32rem 0.72rem;
  border-radius: 18px;
  border: 1px solid var(--tut-border);
  background: transparent;
  color: var(--tut-soft);
  cursor: pointer;
  letter-spacing: 0.03em;
  font-weight: 600;
  transition: all 0.15s;
}

.vat-mode-pill:hover { color: var(--tut-text); border-color: var(--tut-accent); }
.vat-mode-pill.active {
  background: rgba(167, 139, 250, 0.16);
  border-color: var(--tut-accent);
  color: var(--tut-accent);
}

/* ── A small inline legend used in widget captions ─────────────── */
.legend-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.85rem;
  font-family: var(--mono);
  font-size: 0.74rem;
  color: var(--tut-muted);
  margin-top: 0.45rem;
}

.legend-row span { display: inline-flex; align-items: center; gap: 0.35rem; }

.legend-swatch {
  width: 12px;
  height: 12px;
  border-radius: 2px;
  display: inline-block;
  box-shadow: 0 0 6px currentColor;
}