function switchTabs (which) {
//--- Switches the tabs

	tabs = document.getElementById ('popular').getElementsByTagName ('div');
	for (i = 0; i < tabs.length; i++) {
		if (tabs[i].className.indexOf ('tab') != -1) {
			tabs[i].className = 'tab';
		}
	}
	which.className = 'tab selected';

}