function gradient(id, level) {
	var box = document.getElementById(id);
	box.style.opacity = level;
	box.style.MozOpacity = level;
	box.style.KhtmlOpacity = level;
	box.style.filter = "alpha(opacity=" + level * 100 + ")";
	box.style.display="block";
	return;
}

function fadein(id) {
	var level = 0;
	while(level <= 1) {
		setTimeout( "gradient('" + id + "'," + level + ")", (level* 1000) + 10);
		level += 0.01;
	}
}

// Open the lightbox

function openbox(fadin) {
	var box = document.getElementById('box-formulaire'); 
	document.getElementById('masque').style.display='block';
	
	if(fadin) {
		gradient("box-formulaire", 0);
		fadein("box-formulaire");
	} else { 	
		box.style.display='block';
	}  	
}

// Close the lightbox

function closebox() {
   document.getElementById('box-formulaire').style.display='none';
   document.getElementById('masque').style.display='none';
}