//allume le champs
////////////////////////////////////////////////////
function high_light(champ){
   	if($(champ)){
   		myFx = new Fx.Morph(champ, {duration: 500, transition: Fx.Transitions.Sine.easeOut}).start('.lighton');
	};
}
// éteind le champ
////////////////////////////////////////////////////
function high_light_off(champ){
   	if($(champ)){
   		myFx = new Fx.Morph(champ, {duration: 500, transition: Fx.Transitions.Sine.easeOut}).start('.lighoff');
	};
}
// affiche le message
function hide_message_display(){
		$("message_display").style.display= "none";
}