/* =============== Banner 轮播核心样式 =============== */
.focus {
    height: 1019px; /* 必须固定高度，不能用 100% */
    position: relative;
    overflow: hidden;
    margin: 0;
    padding: 0;
  }
  
  .focus_m {
    position: relative;
    width: 100%;
    height: 1019px;
    overflow: hidden;
  }
  
  .focus_m ul {
    position: relative;
    width: 100%;
    height: 1019px;
    margin: 0;
    padding: 0;
    list-style: none;
  }
  
  .focus_m li {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 1019px;
    margin: 0;
    padding: 0;
    display: none; /* 初始隐藏 */
  }
  
  .focus_m li:first-child {
    display: block; /* 第一张默认显示 */
  }
  
  /* 小圆点（底部居中） */
  .focus_s {
    position: absolute;
    bottom: 20px;
    left: 50%;
    transform: translateX(-50%);
    z-index: 10;
    margin: 0;
    padding: 0;
    list-style: none;
  }
  
  .focus_s li {
    float: left;
    cursor: pointer;
    width: 15px;
    height: 15px;
    margin: 0 5px;
  }
  
  .focus_s li b {
    display: block;
    width: 15px;
    height: 15px;
    background: #ccc;
    border-radius: 50%;
  }
  
  .focus_s li.active b {
    background: #fff;
    box-shadow: 0 0 0 2px #333;
  }
  
  /* 左右按钮 */
  .focus_l, .focus_r {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    width: 40px;
    height: 40px;
    line-height: 40px;
    text-align: center;
    font-size: 20px;
    color: #fff;
    background: rgba(0, 0, 0, 0.5);
    border-radius: 50%;
    cursor: pointer;
    z-index: 10;
  }
  
  .focus_l { left: 20px; }
  .focus_r { right: 20px; }
  
  .focus_l:hover, .focus_r:hover {
    background: rgba(0, 0, 0, 0.8);
  }
  
  /* 清除 IE hack 干扰 */
  #focus {
    margin-top: 0 !important;
  }
  
  /* 修复图片缩放（确保填满容器） */
  .focus_m img {
    width: 100%;
    height: 1019px;
    object-fit: cover; /* 关键！防止变形 */
    display: block;
  }