function getWindowHeight() {
		var windowHeight = 0;
		if (typeof(window.innerHeight) == 'number') {
			windowHeight = window.innerHeight;
		}
		else {
			if (document.documentElement && document.documentElement.clientHeight) {
				windowHeight = document.documentElement.clientHeight;
			}
			else {
				if (document.body && document.body.clientHeight) {
					windowHeight = document.body.clientHeight;
				}
			}
		}
		return windowHeight;
		}
		
		function setFooter() {
			if (document.getElementById) {
				var windowHeight = getWindowHeight();
				var footerElement = document.getElementById('navgauche');
				footerElement.style.height = windowHeight-230 + 'px';
				var footerElement = document.getElementById('navdroite');
				footerElement.style.height = windowHeight-230 + 'px';
				var footerElement = document.getElementById('conteneur');
				footerElement.style.height = windowHeight-230 + 'px';
				}
			}