function aff_sous_menu(i) {
	if (i==1) { 
		document.getElementById('missions').style.display = "none"; 
		new Effect.Appear(document.getElementById('prestas'), {duration:0.2} ); 
		}
	else { 
		document.getElementById('prestas').style.display = "none"; 
		new Effect.Appear(document.getElementById('missions'), {duration:0.2} ); 
		}
	
	}


function cache_sous_menus() {
		new Effect.Fade(document.getElementById('missions'), {duration:0.2} ); 
		new Effect.Fade(document.getElementById('prestas'), {duration:0.2} ); 
	}
	

function hide_sous_nav(i) { 
	if (i==1) document.getElementById('prestas').style.display = "none"; 
	else document.getElementById('missions').style.display = "none"; 
}