相关疑难解决方法(0)

#box {
  height: 170px;
  width: 270px;
  background: #000;
  font-size: 48px;
  color: #FFF;
  text-align: center;
}

<div id="box">
  Lorem ipsum dolor sit
</div>

<!-- Latest compiled and minified CSS -->
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.4/css/bootstrap.min.css">

<!-- Optional theme -->
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.4/css/bootstrap-theme.min.css">

<!-- Latest compiled and minified JavaScript -->
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.4/js/bootstrap.min.js"></script>
<div class="row">
  <div class="col-xs-5">
    <div style="height:5em;border:1px solid #000">Big</div>
  </div>
  <div class="col-xs-5">
    <div style="height:3em;border:1px solid #F00">Small</div>
  </div>
</div>