实现要求

当在一定屏幕下实现换行显示

 

CSS3实现代码

<style type="text/css">

.mydiv{

background-color: yellow;

width: 20rem;

height: 20rem;

margin: 3rem 3rem;

float: left;

}

.mydiv2{

background-color:green;

width: 20rem;

height: 20rem;

margin: 3rem 3rem;

float: left;

}

@media (min-width:400px) and (max-width:500px) {

.mydiv{

background-color: black;

width: 20rem;

height: 20rem;

margin: 3rem 1rem;

float: left;

}

}

}