// This script handles the "expanding" and "collapsing" of nested Elements
function displayListings (categoryName) {
	// build the reference to the specific Category Title element 
	var categoryTitle= (categoryName + "_title");
	// Determine current status of menu being updated (expanded [display:block] or collapsed [display:none]) 
	var status = (document.getElementById(categoryName).style.display);
	// If it's colla[sed...
	if (status == "none") {
		// "Expand" the category listing by making the contained UL visible
		document.getElementById(categoryName).style.display="block";
		// Update the icon of the related categoryTitle element
		document.getElementById(categoryTitle).style.background="#f7f7f8";
	}
	// Else if it's currently "expanded"...
	else {
		// "Collapse" the category listing by making the contained UL visible
		document.getElementById(categoryName).style.display="none";
		// Update the icon of the related categoryTitle element
		document.getElementById(categoryTitle).style.background="#ffffff";
	}
}