// Definitions
	var available_width = (navigator.appName == "Netscape") ? innerWidth : document.body.clientWidth;
	var available_height = (navigator.appName == "Netscape") ? innerHeight : document.body.clientHeight;
	var isNS = (navigator.appName == "Netscape" && parseInt(navigator.appVersion) >= 4);
	var isMac = (navigator.platform == "MacPPC");