/* ============================================================
   UDEA PAGE
============================================================ */

.page-hero {
  padding: 120px 0 var(--space-xxl);
  border-bottom: 1px solid var(--glass-border);
  background:
    radial-gradient(ellipse 70% 60% at 20% 50%, rgba(71,19,150,.15) 0%, transparent 70%),
    rgba(71,19,150,.04);
}

.page-hero-meta {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--lime-green);
  letter-spacing: 1.5px;
  text-transform: uppercase;
  margin-bottom: var(--space-m);
  display: flex;
  align-items: center;
  gap: var(--space-s);
}
.page-hero-meta::before {
  content: '';
  display: inline-block;
  width: 24px;
  height: 1px;
  background: var(--lime-green);
}

.page-hero-desc {
  max-width: 680px;
  color: var(--dim);
  line-height: 1.85;
  margin-top: var(--space-m);
  font-size: 1rem;
}

/* ── Subjects layout ── */
.subjects-section { padding: var(--space-xxl) 0; }

.subjects-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
  gap: var(--space-xl);
  align-items: start;
}

.subject-card {
  background: var(--glass-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--glass-border);
  border-radius: var(--r-md);
  overflow: hidden;
  box-shadow: var(--shadow-1);
}

.subject-header {
  padding: var(--space-m) var(--space-xl);
  background: rgba(71,19,150,.25);
  border-bottom: 1px solid var(--glass-border);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-m);
}

.subject-name {
  font-weight: 800;
  font-size: 0.95rem;
  color: var(--white);
  line-height: 1.3;
}

.subject-body { padding: var(--space-l) var(--space-xl); }

/* ── Topic link card ── */
.topic-link {
  display: flex;
  align-items: flex-start;
  gap: var(--space-m);
  padding: var(--space-m);
  background: rgba(255,255,255,.03);
  border: 1px solid var(--glass-border);
  border-radius: var(--r-sm);
  text-decoration: none;
  color: inherit;
  transition: all 0.2s;
  margin-bottom: var(--space-m);
}
.topic-link:last-child { margin-bottom: 0; }
.topic-link:hover {
  background: rgba(71,19,150,.18);
  border-color: rgba(71,19,150,.7);
  transform: translateX(5px);
}

.topic-icon {
  width: 38px;
  height: 38px;
  background: rgba(71,19,150,.45);
  border-radius: var(--r-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  font-size: 1rem;
}

.topic-info { flex: 1; min-width: 0; }

.topic-name {
  font-weight: 700;
  font-size: 0.92rem;
  color: var(--white);
  margin-bottom: 3px;
}
.topic-tarea {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--amber);
  letter-spacing: 0.5px;
  margin-bottom: 4px;
}
.topic-desc {
  font-size: 0.8rem;
  color: var(--dim);
  line-height: 1.5;
}

.topic-arrow {
  font-family: var(--font-mono);
  color: var(--lime-green);
  font-size: 0.9rem;
  align-self: center;
  transition: transform 0.2s;
  flex-shrink: 0;
}
.topic-link:hover .topic-arrow { transform: translateX(4px); }

/* ── Empty state ── */
.empty-state {
  padding: var(--space-xl) var(--space-m);
  text-align: center;
}
.empty-state-badge {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--dim);
  border: 1px dashed rgba(136,146,164,.4);
  border-radius: var(--r-sm);
  padding: var(--space-xs) var(--space-l);
  letter-spacing: 1px;
  text-transform: uppercase;
  margin-bottom: var(--space-m);
}
.empty-state-text {
  font-size: 0.85rem;
  color: var(--dim);
  line-height: 1.7;
}

/* ── Responsive ── */
@media (max-width: 768px) {
  .page-hero { padding: 100px 0 var(--space-xl); }
  .subjects-grid { grid-template-columns: 1fr; }
}