css佈局基礎聖盃模式

<div class="content">
	<div class="middle"></div>
	<div class="left"></div>
	<div class="right"></div>
</div>

.content{
	padding:0 200px;
    overflow:hidden;
}

.middle{
  width:100%;
  float:left;
  height:400px;
  background-color:yellow;
}

.left{
  float:left;
  height:400px;
  width:200px;
  background-color:red;
  margin-left:-100%;
  position:relatvie;
  left:-200px;
}

.right{
  float:left;
  height:400px;
  width:200px;
  background-color:blue;
  margin-left:-200px;
  position:relatvie;
  right:-200px;
}