#image_fond {
	position: absolute;
	top: 50%;
	left:50%;
	margin-top: -300px;
	margin-left: -500px;
	width: 1000px;
	height: 600px;
}

.invisible {
	position:absolute;
	left:0px;
	top:-5000px;
	width:1px;
	height:1px;
	overflow:hidden;
}

img{
	text-decoration: none;
	border: none;
}