Vue如何在CSS中使用data定义的数据浅析

<template>
  <div>
    <div class="box" 
    :data-content="obj.desc" 
    :data-percent="obj.percent"></div>
  </div>
</template>

<script>
  export default {
    data() {
      return {
        obj: {
          percent: '30%',
          desc: '哈哈哈哈哈哈'
        }
      }
    },
  }
</script>

<style>
.box {
  width: 400px;
  height: 200px;
  border: 1px solid salmon;
  position: relative;
}
.box::before, .box::after {
  position: absolute;
  top: 0; bottom: 0;
}
.box::before {
  content: attr(data-content);
  left: 0;
  right: calc(100% - attr(data-percent));
  background-color: deepskyblue;
}
.box::after {
  content: attr(data-content);
  right: 0;
  left: attr(data-percent);
  background-color: deeppink;
}
</style>

<template>
  <div>
    <div class="box" 
    :style="{'--percent': obj.percent}"
    :data-content="obj.desc" 
    :data-percent="obj.percent"></div>
  </div>
</template>
<style>
  .box {
    width: 400px;
    height: 200px;
    border: 1px solid salmon;
    position: relative;
  }
  .box::before, .box::after {
    position: absolute;
    top: 0; bottom: 0;
  }
  .box::before {
    content: attr(data-content);
    left: 0;
    /* right: calc(100% - attr(data-percent)); */
    right: calc(100% - var(--percent));
    background-color: deepskyblue;
  }
  .box::after {
    content: attr(data-content);
    right: 0;
    /* left: attr(data-percent); */
    left: var(--percent);
    background-color: deeppink;
  }
  </style>