/* 全局设置 */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  background-color: #0a0a0a;
  color: #ffffff;
  /* 默认使用等线风格字体 */
  font-family: "Microsoft YaHei", "PingFang SC", "Heiti SC", sans-serif;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  overflow-x: hidden;
  /* 防止背景图撑开横向滚动条 */
}

/* 导航栏 (保持一致) */
.navbar {
  height: 60px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 0 24px;
  background-color: #0a0a0a;
  position: relative;
  border-bottom: 1px solid #1a1a1a;
  z-index: 100;
}

.nav-left,
.nav-right {
  width: auto;
}

.nav-left .back-btn {
  background: none;
  border: none;
  color: #ccc;
  font-size: 14px;
  font-family: "Microsoft YaHei", sans-serif;
  display: flex;
  align-items: center;
  gap: 8px;
  cursor: pointer;
}

.nav-left .back-btn:hover {
  color: #fff;
}

.nav-center {
  position: absolute;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%);
  text-align: center;
}

.brand-title {
  font-size: 16px;
  font-weight: 500;
  color: #fff;
  font-family: "SimSun", serif;

}

.brand-subtitle {
  font-size: 10px;
  color: #fff;
  letter-spacing: 2px;
  margin-top: 2px;
}

.nav-right {
  display: flex;
  gap: 16px;
}

.nav-link {
  font-size: 15px;
  color: #999;
  text-decoration: none;
  padding: 6px 12px;
  border-radius: 4px;
  transition: all 0.2s;
}

.nav-link:hover,
.nav-link.active {
  background-color: #00b386;
  color: #fff;
}

/* --- 背景装饰层 --- */
.bg-layer {

  position: fixed;
  top: 55%;
  right: 0;
  transform: translateY(-50%);
  /* 垂直居中对齐 */

  /* 控制图片大小区域，占比与 flow-his 相同 */
  width: 50vw;
  height: 80vh;

  /* 背景图设置：请根据实际路径替换 */
  background-image: url('./素材补充/图案.png');
  background-size: contain;
  background-repeat: no-repeat;
  background-position: center right;
  /* 图片靠右对齐 */

  pointer-events: none;
  /* 让鼠标穿透，不影响操作 */
  z-index: 0;
  opacity: 0.9;

  /* 渐变黑影遮罩（保留了原来好看的边缘融入感） */
  mask-image: linear-gradient(to left, rgba(0, 0, 0, 1), rgba(0, 0, 0, 0.2));
  -webkit-mask-image: linear-gradient(to left, rgba(0, 0, 0, 1), rgba(0, 0, 0, 0.2));

  /* 增加与 flow-his 完全一致的动感呼吸动画 */
  animation: pulseGlow 10s infinite alternate;
}



/* 呼吸浮动动画 */
@keyframes pulseGlow {
  0% {
    /* 注意: 需要带上 translateY 避免发生位置跳变 */
    transform: translateY(-50%) scale(1);
    opacity: 0.6;
  }

  100% {
    transform: translateY(-50%) scale(1.1);
    opacity: 0.9;
  }
}

/* 手机端适配：隐藏背景图 */
@media (max-width: 768px) {
  .bg-layer {
    display: none;
  }

  .timeline-container {
    margin-left: 20px;
  }
}

/* --- 主内容区 --- */
.main-container {
  position: relative;
  z-index: 1;
  /* 确保文字在背景之上 */
  max-width: 1200px;
  margin: 0 auto;
  padding: 60px 24px;
  width: 100%;
  display: flex;
  flex-direction: column;
}

/* 头部 */
.history-header {
  text-align: center;
  margin-bottom: 60px;
}

.page-title {
  font-family: "SimSun", "Songti SC", serif;
  /* 宋体 */
  font-size: 42px;
  font-weight: 800;
  /* 字重加粗 */
  /* 绿色到黄色渐变 */

  background: linear-gradient(90deg, #6ab9a5 30%, #f9d500 70%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;

  margin-bottom: 12px;
}

.page-subtitle {
  /* 等线、白色、14px */
  font-family: "Microsoft YaHei", sans-serif;
  font-size: 14px;
  color: #fff;
}

/* --- 时间轴容器 --- */
.timeline-container {
  position: relative;
  max-width: 700px;
  /* 限制宽度，不让文字跑得太远遮住背景圆盘 */
  margin-left: 100px;
  /* 整体居左，留出左边距 */
  padding-left: 30px;
  /* 给竖线留位置 */
}

/* 竖着的绿色渐变线图片 */
.timeline-axis-img {
  position: absolute;
  left: -70px;
  top: -62px;
  width: 153px;
  height: 70%;
  object-fit: fill;
}

/* 单个时间节点 */
.timeline-item {
  position: relative;
  margin-bottom: 48px;
  /* 间距 */
  opacity: 0;
  /* 初始隐藏，给JS做动画 */
  transform: translateY(20px);
}

/* 绿色小圆球 */
.timeline-dot {
  position: absolute;
  left: -32px;
  /* (padding-left 30) + (自身宽度一半) 调整对齐线 */
  top: 6px;
  width: 8px;
  height: 8px;
  background-color: #00b386;
  border-radius: 50%;
  box-shadow: 0 0 8px rgba(0, 179, 134, 0.8);
  z-index: 2;
}



/* 标题样式 */
.period-title {
  font-family: "Microsoft YaHei", sans-serif;
  /* 等线 */
  font-size: 22px;
  font-weight: 500;
  /* 字重中等 */
  margin-bottom: 6px;
}

/* 青色标题 */
.cyan-text {
  color: #e3c478;
  /* 青色/天蓝色 */
  text-shadow: 0 0 5px rgba(0, 229, 255, 0.3);
  font-family: "SimSun", "宋体", "Songti SC", "Noto Serif SC", serif;
}

/* 黄色标题 */
.yellow-text {
  color: #e3c478;
  /* 黄色 */
  text-shadow: 0 0 5px rgba(249, 213, 0, 0.3);
  font-family: "SimSun", "宋体", "Songti SC", "Noto Serif SC", serif;
}

/* 正文描述 */
.period-desc {
  font-family: "Microsoft YaHei", sans-serif;
  /* 等线 */
  font-size: 15px;
  color: #b3b2b2;
  /* 灰色 */
  line-height: 1.6;
  text-align: justify;
}

/* 响应式适配 */
@media (max-width: 768px) {
  .bg-plate {
    right: -20%;
    opacity: 0.3;
    /* 手机端淡化背景 */
  }

  .timeline-container {
    margin-left: 20px;
  }
}

/* =========================================
   移动端与平板响应式设计 (完美流式布局)
========================================= */
@media screen and (max-width: 1024px) {

  /* 1. 解除页面高度锁定，允许上下滚动 */
  body {
    height: auto;
    overflow-y: auto;
    min-height: 100vh;
  }

  /* 2. 导航栏重排：不拥挤的两行布局 */
  .navbar {
    height: auto;
    padding: 12px 16px;
    flex-wrap: wrap;
    /* 允许换行 */
  }

  .nav-left {
    flex: 1;
    /* 返回按钮靠左 */
  }

  .nav-center {
    position: static;
    transform: none;
    flex: 1;
    text-align: center;
  }

  /* 导航链接放到第二行，并允许横向滑动 */
  .nav-right {
    width: 100%;
    margin-top: 16px;
    display: flex;
    justify-content: flex-start;
    gap: 12px;
    overflow-x: auto;
    /* 超出屏幕可横向滑动 */
    padding-bottom: 8px;
    /* 给滑动条留一点空间 */
    -webkit-overflow-scrolling: touch;
    /* 丝滑滚动 */
  }

  /* 隐藏横向滚动条保持美观 */
  .nav-right::-webkit-scrollbar {
    display: none;
  }

  .nav-link {
    white-space: nowrap;
    /* 文字不换行 */
  }

  /* 3. 页面主容器 */
  .main-container {
    padding: 16px;
    height: auto;
    overflow: visible;
  }

  /* 4. 核心内容排版：严格按照 上->下 顺序 */
  .content-wrapper {
    flex-direction: column;
    /* 变为上下结构 */
    height: auto;
    overflow: visible;
    gap: 24px;
  }

}