$(document).ready(function() {	

	var activePopup = "";

	$('a#popup_trigger').click(function() {
		showPopup('div#popup');
		return false;
	});
	
	$('a.close_popup').click(function() {
		hidePopup();
		return false;
	});
	
	function showPopup(popupid){
		
		if(activePopup) {
			hidePopup();
		};
		
		$(popupid).fadeIn("fast");		
		
		activePopup = popupid;
	}
	
	function hidePopup() {
		$(activePopup).fadeOut("fast");
	}

});