#global {
position:absolute;
width: 955px;
height: 600px;
left: 50%;
top: 50%;
margin-top: -300px;
margin-left: -477px;
}
body {
	background-color: #4694d2;
	margin-left: 0px;
	margin-top: 0px;
	margin-right: 0px;
	margin-bottom: 0px;
}
#central {
position:absolute;
width: 450px;
height: 600px;
left: 50%;
top: 50%;
margin-top: -300px;
margin-left: -225px;
}
#milieu {
position:absolute;
width: 600px;
height: 600px;
left: 50%;
top: 50%;
margin-top: -300px;
margin-left: -300px;
}
#posit {
position:absolute;
width: 450px;
height: 450px;
left: 50%;
top: 50%;
margin-top: -225px;
margin-left: -225px;
}