element样式用的是类选择器,但是为什么能对于标签内容进行修改呀

个人是学习后端的.因为做项目在学习vue中写点项目,用element后有这个问题,希望能解答

例如el-row 不用是标签选择器吗,这里是类选择器

<el-row type="flex" class="row-bg">
  <el-col :span="6"><div class="grid-content bg-purple"></div></el-col>
  <el-col :span="6"><div class="grid-content bg-purple-light"></div></el-col>
  <el-col :span="6"><div class="grid-content bg-purple"></div></el-col>
</el-row>
<el-row type="flex" class="row-bg" justify="center">
  <el-col :span="6"><div class="grid-content bg-purple"></div></el-col>
  <el-col :span="6"><div class="grid-content bg-purple-light"></div></el-col>
  <el-col :span="6"><div class="grid-content bg-purple"></div></el-col>
</el-row>
<el-row type="flex" class="row-bg" justify="end">
  <el-col :span="6"><div class="grid-content bg-purple"></div></el-col>
  <el-col :span="6"><div class="grid-content bg-purple-light"></div></el-col>
  <el-col :span="6"><div class="grid-content bg-purple"></div></el-col>
</el-row>
<el-row type="flex" class="row-bg" justify="space-between">
  <el-col :span="6"><div class="grid-content bg-purple"></div></el-col>
  <el-col :span="6"><div class="grid-content bg-purple-light"></div></el-col>
  <el-col :span="6"><div class="grid-content bg-purple"></div></el-col>
</el-row>
<el-row type="flex" class="row-bg" justify="space-around">
  <el-col :span="6"><div class="grid-content bg-purple"></div></el-col>
  <el-col :span="6"><div class="grid-content bg-purple-light"></div></el-col>
  <el-col :span="6"><div class="grid-content bg-purple"></div></el-col>
</el-row>

<style>
  .el-row {
    margin-bottom: 20px;
    &:last-child {
      margin-bottom: 0;
    }
  }
  .el-col {
    border-radius: 4px;
  }
  .bg-purple-dark {
    background: #99a9bf;
  }
  .bg-purple {
    background: #d3dce6;
  }
  .bg-purple-light {
    background: #e5e9f2;
  }
  .grid-content {
    border-radius: 4px;
    min-height: 36px;
  }
  .row-bg {
    padding: 10px 0;
    background-color: #f9fafc;
  }
</style>

<el-row>和<el-col>是element的模板中的标签，
模板中的标签不能被浏览器直接解析，
到浏览器中是先经过vue把模板中的标签转变成原生html的<div>元素
el-row和el-col会添加到div的class属性中。
在经过vue生成的页面中是没有el-row和el-col标签的。

比如

<el-row :gutter="20">
  <el-col :span="6"><div class="grid-content bg-purple"></div></el-col>
  <el-col :span="6"><div class="grid-content bg-purple"></div></el-col>
  <el-col :span="6"><div class="grid-content bg-purple"></div></el-col>
  <el-col :span="6"><div class="grid-content bg-purple"></div></el-col>
</el-row>

到浏览器中会转变成这样

所以在css中就要用类选择器

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