<!-- Fonction pour changer afficher l'image de fond au premier plan -->
function afficherFond() {

	varTexte = document.getElementById('texte'); 	
	varMenu = document.getElementById('cadreMenu');
	varLienMentions = document.getElementById('lienMentions');
	varLogo = document.getElementById('logo');
	
	
	if (document.getElementById('imgFond').style.zIndex == '0') {
		
		document.getElementById('imgFond').style.zIndex = '100';

			varTexte.style.opacity ='0.5';
			varMenu.style.opacity ='0.5';
			varLienMentions.style.opacity ='0.5';
			varLogo.style.opacity ='0.5';
			
			varTexte.style.MozOpacity = '0.5';
			varMenu.style.MozOpacity = '0.5';
			varLienMentions.style.MozOpacity = '0.5';		
			varLogo.style.MozOpacity = '0.5';			

	}
	else {
		document.getElementById('imgFond').style.zIndex = '0';

		varTexte.style.opacity = '1';
		varMenu.style.opacity = '1';
		varLienMentions.style.opacity = '1';		
		varLogo.style.opacity = '1';		
		
		varTexte.style.MozOpacity='1';
		varMenu.style.MozOpacity='1';
		varLienMentions.style.MozOpacity='1';
		varLogo.style.MozOpacity='1';
			
	}
}