/* ==========================================================================
   CHALLENGES
   ========================================================================== */

.challenge-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(360px, 1fr));
  gap: var(--space-md);
}

.challenge-card {
  background: var(--bg-surface);
  border-radius: var(--radius-md);
  padding: var(--space-lg);
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--card-border);
}

.challenge-card--inactive { opacity: 0.6; }

.challenge-card__header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: var(--space-sm);
}

.challenge-card__name {
  font-family: var(--font-display);
  font-size: 1rem;
  font-weight: 500;
  font-variation-settings: 'opsz' 20;
}

.challenge-card__badge {
  font-size: 0.625rem;
  font-weight: 600;
  color: var(--completed);
  background: rgba(61, 124, 71, 0.08);
  padding: 2px 8px;
  border-radius: 100px;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.challenge-card__badge--ended {
  color: var(--text-muted);
  background: var(--bg-warm);
}

.challenge-card__desc {
  font-size: 0.8125rem;
  color: var(--text-secondary);
  margin-bottom: var(--space-md);
  line-height: 1.5;
}

.challenge-card__meta {
  display: flex;
  gap: var(--space-md);
  flex-wrap: wrap;
  font-size: 0.75rem;
  color: var(--text-muted);
  margin-bottom: var(--space-md);
}

.challenge-card__goal {
  color: var(--accent);
  font-weight: 600;
}

.challenge-card__participants {
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
}

.challenge-card__empty {
  font-size: 0.8125rem;
  color: var(--text-faint);
  font-style: italic;
}

.challenge-participant {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.challenge-participant__info {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.challenge-participant__avatar {
  width: 20px;
  height: 20px;
  border-radius: 50%;
  object-fit: cover;
}

.challenge-participant__avatar--placeholder { background: var(--bg-inset); }

.challenge-participant__name {
  font-size: 0.8125rem;
  font-weight: 500;
  color: var(--text);
  flex: 1;
}

.challenge-participant__count {
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  color: var(--text-muted);
}

.challenge-participant__books {
  display: flex;
  flex-wrap: wrap;
  gap: 4px;
  margin-top: 4px;
  padding-left: 28px;
}

.challenge-participant__book {
  font-size: 0.6875rem;
  color: var(--text-secondary);
  background: var(--bg-warm);
  padding: 2px 8px;
  border-radius: 3px;
}

.challenge-participant__book--clickable {
  cursor: pointer;
  transition: var(--transition);
}

.challenge-participant__book--clickable:hover {
  background: var(--accent-light);
  color: var(--accent);
}