body,html{
	margin:0;
	padding:0;
}
div.back, div.backin , div.bottom{
	width:100%;
	margin:0;
	padding:0;
}
div.middle, div.bottomin{
	margin:auto;
}
div.right{
	float:right;
}
div.left{
	float:left;
}
div.clear{
	clear:both;
}