#conteneur {
	position: absolute;
	width: 900px;
	left: 50%;
	margin-left: -450px;
	margin-top:50px;
	background:#FFFFFF;
}
#bt1 {
	position:absolute;
	top:387px;
	left:165px;
}
#bt2 {
	position:absolute;
	top:475px;
	left:165px;
}
img {
	border:none;
}