请问下怎么把带有active标签的项目显示到顶部的标题处

Question

<ul>
<li class="li_01">

<div class="select"><span>标题</span>
  <dl>
    <dd>选项一</dd>
    <dd class="active">选项二</dd>
    <dd>选项三</dd>
  </dl>
</div>

</li>

<li class="li_02">

<div class="select"><span>标题</span>
  <dl>
    <dd>选项一</dd>
    <dd>选项二</dd>
    <dd class="active">选项三</dd>
  </dl>
</div>

</li>
</ul>

Answer 1

获取类名为active的dom的文本值:
var activeText = document.querySelector('.li_01 .select dl .active').innerText
获取<span>标题</span>的dom并赋值：
document.querySelector('.li_01 .select span').innerText = activeText
li_02同理