<div class="box">
<ul class="clearfix">
<li>1</li>
<li>2</li>
</ul>
<p>今天天气很晴朗</p>
</div>
.box{
}
.box ul{
backgroud: red;
}
.clearfix{
}
.clearfix:after{
display: block;
content: '';
height: 0;
clear: both;
}
.box li{
float: left;
width: 120px;
height: 40px;
background: #dbdbdb;
margin: 10px;
}