onscroll = function(){
		
		if(window.innerHeight){ height = window.innerHeight;
		}else{ height = document.getElementById("test_longueur").height; }
		
		heightCommande = document.getElementById("commande").offsetHeight+25;
		marge = height-heightCommande;

		if(marge<=0){
			document.getElementById("commandeHaut").style.top = 231+"px";
			document.getElementById("commande").style.top = 256+"px";
		}else{		
			if(document.body.scrollTop){
				if(document.body.scrollTop<=231){
					document.getElementById("commandeHaut").style.top = 231+"px";
					document.getElementById("commande").style.top = 256+"px";
				}else{
					document.getElementById("commandeHaut").style.top = document.body.scrollTop+"px";
					document.getElementById("commande").style.top = (document.body.scrollTop+25)+"px";
				}
			}else{
				if(document.documentElement.scrollTop<=231){
					document.getElementById("commandeHaut").style.top = 231+"px";
					document.getElementById("commande").style.top = 256+"px";
				}else{
					document.getElementById("commandeHaut").style.top = document.documentElement.scrollTop+"px";
					document.getElementById("commande").style.top = (document.documentElement.scrollTop+25)+"px";
				}
				
			}
		
		}			
    }