/* =============================================
   QUIZPREP — Quiz Selection Screen
   Stage 2
   ============================================= */

/* ── Page Header ── */
.qs-header {
  background: var(--color-primary);
  color: var(--color-white);
  padding: var(--space-xl) 0 var(--space-lg);
  text-align: center;
}

.qs-header__title {
  font-size: var(--fs-2xl);
  font-weight: 700;
  margin-bottom: var(--space-xs);
}

.qs-header__sub {
  color: rgba(255, 255, 255, 0.8);
  font-size: var(--fs-base);
  margin-bottom: var(--space-md);
}

/* ── Filter Buttons ── */
.qs-filters {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: var(--space-xs);
}

.filter-btn {
  padding: 0.5rem 1.25rem;
  border-radius: 999px;
  border: 2px solid rgba(255, 255, 255, 0.4);
  background: transparent;
  color: var(--color-white);
  font-size: var(--fs-sm);
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition);
}

.filter-btn:hover {
  border-color: var(--color-white);
  background: rgba(255, 255, 255, 0.1);
}

.filter-btn.active {
  background: var(--color-accent);
  border-color: var(--color-accent);
  color: var(--color-primary);
  font-weight: 700;
}

/* ── Subject Card Grid ── */
.qs-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: var(--space-md);
}

/* ── Subject Card ── */
.subject-card {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-lg);
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: var(--space-sm);
  transition: all var(--transition);
  box-shadow: var(--shadow);
}

.subject-card:hover {
  border-color: var(--color-primary);
  transform: translateY(-4px);
  box-shadow: 0 8px 24px rgba(26, 94, 58, 0.12);
}

.subject-card__icon {
  font-size: 2.25rem;
  line-height: 1;
}

.subject-card__info {
  flex: 1;
}

.subject-card__name {
  font-size: var(--fs-lg);
  font-weight: 700;
  color: var(--color-primary);
  margin-bottom: 4px;
}

.subject-card__meta {
  font-size: var(--fs-sm);
  color: var(--color-text-muted);
}

.subject-card__btn {
  width: 100%;
  text-align: center;
  margin-top: auto;
}

/* ── Hidden / Empty state ── */
.hidden { display: none; }

.qs-empty {
  text-align: center;
  color: var(--color-text-muted);
  font-size: var(--fs-lg);
  padding: var(--space-2xl) 0;
}

/* ── Filtered-out cards ── */
.subject-card.filtered {
  display: none;
}