/* ============================================================
   柏林墙专题页 — 在冷战专题样式基础上的视觉微调
   继续使用 modern 主题钢蓝色调，增加“混凝土墙 / 涂鸦 / 分裂线”意象
   ============================================================ */

.berlin-wall-hero .topic-hero__overlay {
  background: linear-gradient(
    180deg,
    rgba(20, 38, 50, 0.28) 0%,
    rgba(33, 58, 73, 0.70) 55%,
    rgba(22, 38, 50, 0.94) 100%
  );
}

.berlin-wall-hero::after {
  content: '';
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(90deg, rgba(255,255,255,0.08) 1px, transparent 1px),
    linear-gradient(0deg, rgba(255,255,255,0.06) 1px, transparent 1px);
  background-size: 72px 56px;
  mix-blend-mode: overlay;
  opacity: 0.42;
  z-index: 1;
}

.berlin-wall-hero .topic-hero__content {
  z-index: 2;
}

.berlin-wall-hero .topic-hero__tag {
  background: linear-gradient(135deg, var(--accent), #5f7f91);
  box-shadow: 0 6px 18px rgba(35, 58, 77, 0.24);
}

.berlin-wall-hero .topic-hero__title {
  text-shadow: 0 4px 20px rgba(0, 0, 0, 0.28);
}

/* “分裂线”章节标题装饰 */
.topic-section__header {
  position: relative;
}

.topic-section__header::after {
  content: '';
  display: block;
  width: 72px;
  height: 3px;
  margin-top: var(--spacing-sm);
  border-radius: 3px;
  background: linear-gradient(90deg, var(--accent), rgba(52, 84, 109, 0.12));
}

.topic-intro .topic-section__header::after,
.topic-conclusion .topic-section__header::after,
.topic-related__header::after {
  display: none;
}

/* 柏林墙专题数据卡：沿用布局，调整顶部色带 */
.berlin-data-grid .topic-data-card:nth-child(1)::before { background: #34546D; }
.berlin-data-grid .topic-data-card:nth-child(2)::before { background: #6F7D86; }
.berlin-data-grid .topic-data-card:nth-child(3)::before { background: #9D2933; }

/* 建墙日历使用更冷峻的墙体底色 */
.berlin-calendar {
  background:
    linear-gradient(135deg, rgba(52, 84, 109, 0.06), rgba(255, 255, 255, 0.36)),
    var(--color-card-bg);
}

.berlin-calendar .topic-crisis-day {
  position: relative;
  overflow: hidden;
}

.berlin-calendar .topic-crisis-day::before {
  content: '';
  position: absolute;
  left: 0;
  right: 0;
  top: 0;
  height: 3px;
  background: rgba(52, 84, 109, 0.28);
}

/* 东西柏林对照表：突出中线 */
.berlin-compare .topic-compare__col--center {
  border-left: 1px solid var(--color-border);
  border-right: 1px solid var(--color-border);
  background: rgba(52, 84, 109, 0.05);
}

.berlin-compare .topic-compare__header .topic-compare__col--center {
  background: rgba(255, 255, 255, 0.12);
  color: var(--color-white);
  border-color: rgba(255, 255, 255, 0.18);
}

/* 逃亡故事卡片：轻微错落感 */
.berlin-story-grid .topic-war-card {
  min-height: 230px;
}

.berlin-story-grid .topic-war-card__region {
  background: rgba(52, 84, 109, 0.10);
  color: var(--accent);
}

.berlin-story-grid .topic-war-card:nth-child(2n) .topic-war-card__region {
  background: rgba(157, 41, 51, 0.10);
  color: #9D2933;
}

/* 移动端微调 */
@media (max-width: 768px) {
  .berlin-wall-hero::after {
    background-size: 48px 40px;
  }

  .topic-section__header::after {
    width: 56px;
  }

  .berlin-story-grid .topic-war-card {
    min-height: auto;
  }
}