效果一
<body>
<div class="container">
<img src="img/pic01.jpg" class="img-responsive" />
<hr />
<img src="img/pic01.jpg" width="150" height="150" class="img-rounded" />
<img src="img/pic01.jpg" width="150" height="150" class="img-circle" />
<img src="img/pic01.jpg" width="150" height="150" class="img-thumbnail" />
<hr />
<p class="text-danger">大家好</p>
<p class="text-info">大家好</p>
<p class="text-primary">大家好</p>
<hr />
<p class="bg-info text-danger">大家好</p>
<hr/>
<button type="button" class="close">×</button>
<a href="#" class="close">×</a>
<hr />
<span class="caret"></span>
</body>
效果二
<body>
<div class="center-block">
居中
</div>
<div>
<div class="pull-left" style="width:200px;">居左</div>
<div class="pull-right" style="width: 200px;">居右</div>
<div class="clearfix visible-sm"></div>
<div class=" visible-sm">ccc</div>
</div>
</body>