/* 整体布局容器 */
    .category-container {
      display: flex;
      height: 100vh;
    }

    /* 左侧一级导航栏（25%宽度，固定） */
    .category-left {
      width: 25%;
      height: 100%;
      overflow-y: auto; /* 一级菜单过多时可滚动 */
      position: fixed; /* 固定不动 */
      top: 0;
      left: 0;
      z-index: 99;
      box-shadow: inset 0 2px 4px rgba(0, 0, 0, 0.11);
      padding: 64px 0 128px 0;
      background: rgba(235,235,235,0.3);
    backdrop-filter: blur(10px);
    }
    .first-menu-item {
      height: 48px;
      line-height: 48px;
      padding: 0 16px;
      color: #333;
      font-size: 14px;
      text-decoration: none;
      display: block;
      border-right: 4px solid transparent;
      transition: background 0.2s ease;
      display: flex;
      align-items: center;
    }
    .first-menu-item.active {
      background: #990000;
      border-right-color: #333;
      color: #ffffff;
      font-weight: 600;
    }
    .first-menu-item:active {
      background: #eee;
    }

    /* 右侧二级菜单区域（75%宽度，可滚动） */
    .category-right {
      width: 75%;
      margin-left: 25%; /* 避开左侧固定栏 */
      padding: 16px;
      overflow-y: auto; /* 内容过长可向下滚动 */
      height: 100vh;
      background: #fff;
    }

    /* 二级菜单头部（一级图标+标题+更多链接） */
    .second-menu-header {
      display: flex;
      justify-content: space-between;
      align-items: center;
      margin-bottom: 20px;
      padding-bottom: 12px;
      border-bottom: 1px dashed #ccc;
    }
    .header-left {
      display: flex;
      align-items: center;
      gap: 8px;
    }
    .first-menu-icon {
      width: 24px;
      height: 24px;
      border-radius: 4px;
      overflow: hidden;
    }
    .first-menu-icon img {
      width: 100%;
      height: 100%;
      object-fit: cover;
    }
    .first-menu-title {
      font-size: 16px;
      color: #333;
    }
    .header-right a {
      font-size: 13px;
      color: #333;
      text-decoration: none;
    }

    /* 二级菜单列表（一行三个） */
    .second-menu-list {
      display: grid;
      grid-template-columns: repeat(3, 1fr); /* 一行三个 */
      gap: 18px 12px
    }
    .second-menu-item {
      text-decoration: none;
      display: flex;
      flex-direction: column;
      align-items: center;
    }
    .second-menu-img {
      width: 100%;
      aspect-ratio: 1/1; /* 正方形图片 */
      border-radius: 8px;
      overflow: hidden;
      position: relative; /* 用于小图标定位 */
      margin-bottom: 8px;
      background: rgba(235,235,235,0.85);
    backdrop-filter: blur(10px);
    }
    .second-menu-img img {
      width: 100%;
      height: 100%;
      object-fit: cover;
    }
    /* 图片右下角小图标 */
    .img-corner-icon {
      position: absolute;
      bottom: 4px;
      right: 4px;
      width: 16px;
      height: 16px;
      background: url("../images/touch.png") no-repeat center;
      background-size: 100%;
    }
    .second-menu-name {
      font-size: 12px;
      color: #333;
      text-align: center;
      line-height: 1.4;
    }

    /* 响应式适配（移动端） */
    @media (max-width: 750px) {
      .category-left {
        width: 28%; /* 移动端微调宽度 */
      }
      .category-right {
        width: 72%;
        margin-left: 28%;
      }
      .second-menu-list {
        gap: 18px 12px;
      }
    }