2.图片自适应盒子不拉伸

    .img-cantainer {
        position: relative;
        width: 550px;
        height: 300px;
        overflow: hidden;
        border-radius: 20px;
       img {
            position: absolute;
              top: 50%;
            transform: translateY(-50%);
            min-height: 100%;
            min-width: 100%;
        }
    }