/* ═══════════════════════════════════════════════════════════════════════════
 * Build a Game Engine · hub page
 * Reuses the shared design tokens from tutorial.css / style.css.
 * ═══════════════════════════════════════════════════════════════════════════ */

/* ── Inline status pills (used in prose) ─────────────────────────────────── */
.status-pill {
  display: inline-block;
  font-size: 0.72em;
  font-weight: 700;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  padding: 0.08em 0.5em;
  border-radius: 999px;
  vertical-align: middle;
  white-space: nowrap;
}
.status-pill.is-built  { color: #0d2a20; background: var(--tut-success); }
.status-pill.is-planned {
  color: var(--tut-muted);
  background: transparent;
  border: 1px dashed var(--tut-border);
}

/* ── Subsystem map (the layer stack) ─────────────────────────────────────── */
.subsystem-map {
  display: flex;
  flex-direction: column;
  gap: 6px;
  margin: 1.5rem 0 0.75rem;
}
.subsystem-map .layer {
  display: flex;
  align-items: baseline;
  gap: 1rem;
  flex-wrap: wrap;
  padding: 0.85rem 1.1rem;
  border: 1px solid var(--tut-border);
  border-left: 3px solid var(--tut-border);
  border-radius: 10px;
  background: var(--tut-surface);
  color: var(--tut-text);
  text-decoration: none;
  transition: transform 0.12s ease, border-color 0.12s ease, background 0.12s ease;
}
.subsystem-map .layer:hover,
.subsystem-map .layer:focus-visible {
  transform: translateX(4px);
  border-left-color: var(--tut-accent);
  background: var(--tut-surface-2);
  outline: none;
}
.subsystem-map .layer-label {
  font-weight: 700;
  font-size: 0.95rem;
  min-width: 9.5rem;
  color: var(--tut-text);
}
.subsystem-map .layer-systems {
  font-size: 0.86rem;
  color: var(--tut-muted);
}
/* Tint the stack from the player-facing top down to the metal. */
.subsystem-map .layer.is-game     { border-left-color: var(--tut-accent); background: var(--tut-accent-glow); }
.subsystem-map .layer.is-frame    { border-left-color: var(--tut-info); }
.subsystem-map .layer.is-core     { border-left-color: var(--tut-success); }
.subsystem-map .layer.is-platform { border-left-color: var(--tut-warn); }

/* ── Phases ──────────────────────────────────────────────────────────────── */
.phase {
  margin: 2rem 0;
  scroll-margin-top: 5rem;
}
.phase-head {
  display: flex;
  align-items: baseline;
  flex-wrap: wrap;
  gap: 0.5rem 0.9rem;
  margin-bottom: 0.9rem;
  padding-bottom: 0.5rem;
  border-bottom: 1px solid var(--tut-border-soft);
}
.phase-num {
  font-family: var(--mono);
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--tut-accent);
  background: var(--tut-accent-glow);
  padding: 0.2em 0.6em;
  border-radius: 999px;
}
.phase-title {
  margin: 0;
  font-size: 1.2rem;
  color: var(--tut-text);
}
.phase-note {
  font-size: 0.86rem;
  color: var(--tut-muted);
}

/* ── Module cards ────────────────────────────────────────────────────────── */
.module-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(248px, 1fr));
  gap: 0.8rem;
}
.module-card {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
  padding: 0.95rem 1rem 1rem;
  border: 1px solid var(--tut-border);
  border-radius: 12px;
  background: var(--tut-surface);
  text-decoration: none;
  min-height: 6.2rem;
}
.module-card.is-built {
  cursor: pointer;
  transition: transform 0.12s ease, border-color 0.12s ease, box-shadow 0.12s ease;
}
.module-card.is-built:hover,
.module-card.is-built:focus-visible {
  transform: translateY(-3px);
  border-color: var(--tut-accent);
  box-shadow: 0 8px 24px -12px var(--tut-accent-glow);
  outline: none;
}
.module-card.is-planned {
  border-style: dashed;
  background: transparent;
  cursor: default;
}
.module-status {
  align-self: flex-start;
  font-size: 0.66rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  padding: 0.12em 0.5em;
  border-radius: 999px;
}
.module-card.is-built .module-status   { color: #0d2a20; background: var(--tut-success); }
.module-card.is-planned .module-status { color: var(--tut-muted); border: 1px dashed var(--tut-border); }
.module-title {
  font-size: 1rem;
  font-weight: 700;
  color: var(--tut-text);
  line-height: 1.25;
}
.module-card.is-planned .module-title { color: var(--tut-soft); }
.module-desc {
  font-size: 0.84rem;
  line-height: 1.45;
  color: var(--tut-muted);
}
.module-card.is-built::after {
  content: "→";
  position: absolute;
  top: 0.85rem;
  right: 1rem;
  color: var(--tut-accent);
  opacity: 0;
  transition: opacity 0.12s ease, transform 0.12s ease;
}
.module-card.is-built:hover::after { opacity: 1; transform: translateX(3px); }

/* Milestone bands + capstone cards */
.phase.is-milestone {
  padding: 1.1rem 1.2rem 1.3rem;
  border: 1px solid var(--tut-accent);
  border-radius: 14px;
  background: linear-gradient(180deg, var(--tut-accent-glow), transparent 70%);
}
.phase.is-milestone .phase-num { color: var(--tut-bg); background: var(--tut-accent); }
.module-card.is-capstone { grid-column: 1 / -1; border-color: var(--tut-accent); }

/* ── Dependency-graph widget ─────────────────────────────────────────────── */
.eng-widget {
  margin: 1.5rem 0 0.6rem;
  padding: 0.75rem;
  border: 1px solid var(--tut-border);
  border-radius: 14px;
  background: linear-gradient(180deg, var(--tut-surface), var(--tut-surface-2));
}
.eng-widget canvas {
  display: block;
  width: 100%;
  aspect-ratio: 16 / 10;
  max-height: 480px;
  min-height: 320px;
  border-radius: 10px;
}
.dag-controls {
  display: flex;
  align-items: center;
  gap: 0.8rem;
  flex-wrap: wrap;
  margin-top: 0.7rem;
}
.dag-btn {
  font-family: var(--mono);
  font-size: 0.78rem;
  color: var(--tut-text);
  background: var(--tut-surface-2);
  border: 1px solid var(--tut-border);
  border-radius: 8px;
  padding: 0.35rem 0.7rem;
  cursor: pointer;
  transition: border-color 0.12s ease, color 0.12s ease;
}
.dag-btn:hover { border-color: var(--tut-accent); color: var(--tut-accent); }
.dag-readout {
  font-size: 0.84rem;
  color: var(--tut-muted);
  flex: 1 1 16rem;
}
.dag-readout a { color: var(--tut-accent); }

/* ── The "holds the bar" list ────────────────────────────────────────────── */
.bar-list {
  list-style: none;
  padding: 0;
  margin: 1rem 0;
  display: grid;
  gap: 0.55rem;
}
.bar-list li {
  padding: 0.7rem 0.9rem;
  border-left: 3px solid var(--tut-accent);
  border-radius: 0 8px 8px 0;
  background: var(--tut-surface);
  font-size: 0.9rem;
  line-height: 1.5;
  color: var(--tut-soft);
}
.bar-list strong { color: var(--tut-text); }

@media (max-width: 560px) {
  .subsystem-map .layer-label { min-width: 0; }
  .module-grid { grid-template-columns: 1fr; }
  .eng-widget canvas { aspect-ratio: 4 / 5; max-height: none; }
}