function recenter(){
	//opera Netscape 6 Netscape 4x Mozilla 
	var docwidth = document.documentElement.clientWidth ? document.documentElement.clientWidth : document.body.clientWidth;
	//alert(docwidth);
	if(docwidth<= 1200){
			var decalage = -600 + (1200-docwidth)/2 -100;
			document.getElementById("body").style.margin="0px 0px 0px "+decalage+"px";
			//alert(decalage);
	}
	else document.getElementById("body").style.margin="0px 0px 0px -700px";
}