vant/packages/vant-css/src/image_preview.css

@import './swipe.css';

@component-namespace van {
  @b image-preview {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    overflow: auto;

    @e image {
      display: block;
      position: absolute;
      left: 0;

      @m center {
        width: 100%;
        height: auto;
        top: 50%;
        transform: translate3d(0, -50%, 0);
      }
    }

    .van-image-preview__image--big {
      height: 100%;
      width: auto;
      left: 50%;
      transform: translate3d(-50%, 0, 0);
    }

    .van-swipe {
      height: 100%;
    }
  }
}