.countdown-header {
  text-align: center;
  margin-bottom: 1.5rem;
}

.countdown-header h1 {
  font-size: 2.5rem;
  font-weight: 700;
  margin: 0 0 1rem 0;
  background: linear-gradient(135deg, var(--color-gradient-primary-start) 0%, var(--color-gradient-primary-end) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.countdown-header p {
  color: var(--color-text-medium);
  font-size: 1.1rem;
  margin: 0.5rem 0 0 0;
}

.boards-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: calc(var(--spacing-unit) * 2);
  width: 100%;
}

.boards-grid.hide-others {
  grid-template-columns: 1fr;
  max-width: 500px;
  margin: 0 auto;
  justify-items: center;
}

.board-card {
  background: var(--color-card-background);
  border: 1px solid var(--color-border);
  border-radius: var(--border-radius);
  padding: calc(var(--spacing-unit) * 2);
  transition: all var(--transition-speed) ease, opacity var(--transition-speed) ease;
  cursor: pointer;
}

.board-card.hidden {
  display: none;
}

.board-card.selected {
  border: 3px solid var(--color-primary);
  box-shadow: 0 0 20px rgba(var(--color-primary-rgb), 0.4);
}

.board-card:hover {
  border-color: var(--color-primary);
  box-shadow: 0 0 15px rgba(var(--color-primary-rgb), 0.1);
}

.board-card.selected:hover {
  border-color: var(--color-primary);
  box-shadow: 0 0 20px rgba(var(--color-primary-rgb), 0.4);
}

.board-name {
  font-size: 1.4rem;
  font-weight: 700;
  margin: 0 0 1rem 0;
  color: var(--color-text-dark);
}

.countdown-box {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0.6rem;
  margin-bottom: 1rem;
  width: 100%;
  box-sizing: border-box;
}

.countdown-item {
  background: var(--color-background);
  border: 1px solid var(--color-border);
  border-radius: var(--border-radius);
  padding: 0.8rem 0.5rem;
  text-align: center;
  min-width: 0;
  overflow: hidden;
}

.countdown-number {
  font-size: 2.5rem;
  font-weight: 700;
  color: var(--color-primary);
  margin: 0;
  line-height: 1;
  word-break: break-word;
}

.countdown-label {
  font-size: 0.65rem;
  color: var(--color-text-medium);
  text-transform: uppercase;
  letter-spacing: 0.4px;
  margin-top: 0.3rem;
  font-weight: 600;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.exam-schedule {
  border-top: 1px solid var(--color-border);
  padding-top: 1rem;
}

.exam-list {
  list-style: none;
  padding: 0;
  margin: 0;
}

.exam-list li {
  display: flex;
  flex-direction: column;
  padding: 0.6rem 0;
  border-bottom: 1px solid var(--color-border);
  font-size: 0.9rem;
}

.exam-list li:last-child {
  border-bottom: none;
}

.exam-paper {
  font-weight: 500;
  color: var(--color-text-dark);
  margin-bottom: 0.2rem;
}

.exam-date {
  color: var(--color-text-medium);
  font-size: 0.8rem;
}

.board-card.hidden {
  display: none;
}

@media (max-width: 768px) {
  .countdown-header h1 {
    font-size: 2rem;
  }

  .boards-grid {
    grid-template-columns: 1fr;
  }

  .countdown-box {
    gap: 0.5rem;
  }

  .countdown-number {
    font-size: 1.4rem;
  }

  .countdown-label {
    font-size: 0.6rem;
  }
}