/* 发展历程页面样式 */
.history-section {
  padding: var(--spacing-3xl) 0;
  background-color: var(--color-background);
}

.timeline {
  position: relative;
  padding: var(--spacing-2xl) 0;
}

.timeline::before {
  content: "";
  position: absolute;
  left: 50%;
  transform: translateX(-50%);
  width: 2px;
  height: 100%;
  background-color: var(--color-primary);
}

.timeline-item {
  margin-bottom: var(--spacing-3xl);
  position: relative;
}

.timeline-item:nth-child(odd) .timeline-date {
  text-align: right;
  padding-right: var(--spacing-2xl);
  width: 48%;
}

.timeline-item:nth-child(even) .timeline-date {
  text-align: left;
  padding-left: var(--spacing-2xl);
  width: 48%;
  margin-left: 52%;
}

.timeline-item:nth-child(odd) .timeline-content {
  text-align: left;
  padding-left: var(--spacing-2xl);
  width: 48%;
  margin-left: 52%;
}

.timeline-item:nth-child(even) .timeline-content {
  text-align: right;
  padding-right: var(--spacing-2xl);
  width: 48%;
}

.timeline-date {
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-semibold);
  color: var(--color-primary);
}

.timeline-content {
  background-color: var(--color-background-light);
  padding: var(--spacing-lg);
  border-radius: var(--border-radius-lg);
  box-shadow: var(--box-shadow-md);
}

.timeline-content h3 {
  font-size: var(--font-size-lg);
  margin-bottom: var(--spacing-md);
  color: var(--color-text-dark);
}

.timeline-content p {
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
  line-height: 1.8;
}

@media (max-width: 768px) {
  .timeline::before {
    left: 20px;
  }

  .timeline-item:nth-child(odd) .timeline-date,
  .timeline-item:nth-child(even) .timeline-date {
    text-align: left;
    padding-left: var(--spacing-lg);
    width: 100%;
    margin-left: 0;
  }

  .timeline-item:nth-child(odd) .timeline-content,
  .timeline-item:nth-child(even) .timeline-content {
    text-align: left;
    padding-left: var(--spacing-lg);
    width: 100%;
    margin-left: 0;
  }
}