/*	dynamic-css.js v1.0 <http://www.bobbyvandersluis.com/articles/dynamicCSS.php>
	Copyright 2005 Bobby van der Sluis
	This software is licensed under the CC-GNU LGPL <http://creativecommons.org/licenses/LGPL/2.1/>
	
	This function allows us to apply css rules such as display:none before the page loads.
	This is handy for navigation that has nested lists that we want to hide by default and expand onclick.
	By using this function users with js disabled will see all the items fully expanded while those
	with js enabled will have the visibility turned off without the annoying flash of unstyled content.
	
*/

function createStyleRule(selector, declaration) {
	if (!document.getElementsByTagName || !(document.createElement || document.createElementNS)) return;
	var agt = navigator.userAgent.toLowerCase();
	var is_ie = ((agt.indexOf("msie") != -1) && (agt.indexOf("opera") == -1));
	var is_iewin = (is_ie && (agt.indexOf("win") != -1));
	var is_iemac = (is_ie && (agt.indexOf("mac") != -1));
	if (is_iemac) return; // script doesn't work properly in IE/Mac
	var head = document.getElementsByTagName("head")[0]; 
	var style = (typeof document.createElementNS != "undefined") ?  document.createElementNS("http://www.w3.org/1999/xhtml", "style") : document.createElement("style");
	if (!is_iewin) {
		var styleRule = document.createTextNode(selector + " {" + declaration + "}");
		style.appendChild(styleRule); // bugs in IE/Win
	}
	style.setAttribute("type", "text/css");
	style.setAttribute("media", "screen"); 
	head.appendChild(style);
	if (is_iewin && document.styleSheets && document.styleSheets.length > 0) {
		var lastStyle = document.styleSheets[document.styleSheets.length - 1];
		if (typeof lastStyle.addRule == "object") { // bugs in IE/Mac and Safari
			lastStyle.addRule(selector, declaration);
		}
	}
}