function changeBg(obj) {
	if (obj.className.indexOf('over') != -1) {
		obj.className = 'contentContainer';
	} else {
		obj.className = 'contentContainer over';
	}
}

function followLink(obj) {
	// find link and follow
	var linkNode = obj.getElementsByTagName('A')[0];
	if (linkNode) document.location.href = linkNode.href;
}