css:hover用法（7）元素滑动样式效果

<style lang="scss" scoped>
#page {
  margin: 30px;
  .ikonw {
    height: 10px;
  }
  .box {
    width: 158px;
    height: 38px;
    border-radius: 20px;
  }
  .box a {
    position: relative;
    z-index: 0;
    display: inline-block;
    width: 158px;
    height: 38px;
    line-height: 38px;
    text-align: center;
    color: rgb(71, 6, 118);
    background-color: #b4b8b9;
    border: 1px solid rgb(148, 243, 242);
    border-radius: 20px;
  }
  .box a:after {
    content: "";
    position: absolute;
    z-index: -1;
    top: 0px;
    left: 0px;
    display: inline-block;
    //width: 1%;//左边会有一点点效果
    width: 0%; //左边看不到
    height: 100%;
    background-color: rgb(120, 243, 171);
    border-radius: 20px;