用div+css设计一个页面布局

Answer 1

<style>
.head{
width:100%;
height:60px;
}
.main{
width:70%;
height:400px;
float:left;
}
.main{
width:30%;
height:400px;
float:right;
}
.footer{
width:100%;
height:60px;
}
</style>

<div class ="head">这里是head区域</div>
<div class ="main">这里是主要内容区域</div>
<div class="main_left">这里是右侧区域</div>
<div class="footer">这里是页脚区域</div>

Answer 2

<div>
<div>头部</div>
<div>
<div style="display: inline-block;width:70%;">中左</div>
<div style="display: inline-block;width:30%;">中右</div>
</div>
<div>底部</div>
</div>

追问

怎么知道是70%和30%?