box-sizing屬性可以為三個(gè)值之一：content-box（default）苦酱，border-box掷空，padding-box。
content-box谎替，border和padding不計(jì)算入width之內(nèi)
padding-box扼睬，padding計(jì)算入width內(nèi)
border-box逮栅，border和padding計(jì)算入width之內(nèi)，其實(shí)就是怪異模式了~
<style type="text/css">
.content-box{
box-sizing:content-box;
-moz-box-sizing:content-box;
width: 100px;
height: 100px;
padding: 20px;
border: 5px solid #E6A43F;
background: blue;
}
.padding-box{
box-sizing:padding-box;
-moz-box-sizing:padding-box;
width: 100px;
height: 100px;
padding: 20px;
border: 5px solid #186645;
background: red;
}
.border-box{
box-sizing:border-box;
-moz-box-sizing:border-box;
width: 100px;
height: 100px;
padding: 20px;
border: 5px solid #3DA3EF;
background: yellow;
}
</style>
Image.png
