我有以下HTML代码:
<div class="row">
<div class="col-lg-3">
<div class="panel panel-default">
<div class="panel-body">
Panel 1 (left)
</div>
</div>
</div>
<div class="col-lg-6">
<div class="panel panel-default">
<div class="panel-body">
Panel 2 (center)
</div>
</div>
</div>
</div>
<div class="col-lg-3">
<div class="panel panel-default">
<div class="panel-body">
Panel 3 (right)
</div>
</div>
</div>
</div>
</div>
<div class="row">
<div class="col-lg-3">
<div class="panel panel-default">
<div class="panel-body">
Panel 2-2 (under panel 2)
</div>
</div>
</div>
</div>
最终结果应该像这样:
![](https://i.imgur.com/9mPuNcJ.png)
![](https://i.imgur.com/dMavnu2.png)