<html>
<head>
    <title></title>

    <style>
body{

    margin: 0;
    padding: 0;

}
#all{
    width: 920px;
    height: 1400px;
    margin-left: auto;
    margin-right: auto;
}
#header{
    border-style: dotted;
    border-collapse: red;
    height: 100px;
}

#content1{
    width:300px;
    height:300px;
    border-style: dotted;
    border-color: blue;
    float: left;
}
#content2{
    width:300px;
    height:200px;
    border-style: dotted;
    border-color: green;
    float: left;

}
#content3{
    width:300px;
    height:300px;
    border-style: dotted;
    border-color: purple;
    float: left;

}
#content4{
    width:300px;
    height:200px;
    border-style: dotted;
    border-color: blue;
    float: left;
    clear: both;
}
#content5{
    width:300px;
    height:300px;
    background-color: blue;
    border-style: dotted;
    float: left;



}
#content6{
    width:300px;
    height:200px;
    border-style: dotted;
    border-color: purple;
    float: left;


}
#footer{
    border-style: dotted;
    border-collapse: red;
    height: 100px;
    margin-bottom: 0px;
    clear: both;
}










    </style>
</head>
<body>

<div id='all'>
<div id="header">...</div>
<div id="content1">...</div>
<div id="content2">...</div>
<div id="content3">...</div>
<div id="content4">...</div>
<div id="content5">...</div>
<div id="content6">...</div>
<div id='footer'>...</div>
</div>



















</body>
</html>