.parent_div_1{
    float:left;
    position:relative;
}

.child_div_1{
    float:left;
    position: absolute;
}

.child_div_2{
    float:left;
    width: 480px;
    position:absolute;
    top: 200px;
}

.footer{
    clear:both;
}

html{
	width: 100%;
	height: 100%;
}

body{
	width: 100%;
	height: 100%;
}