//additional properties for jQuery object
$(document).ready(function(){
	//align element in the middle of the screen
	$.fn.alignCenter = function() {
		//get margin left
		var marginLeft = Math.max(40, parseInt($(window).width()/2 - $(this).width()/2)) + 'px';
		//get margin top
		var marginTop = Math.max(40, parseInt($(window).height()/2 - $(this).height()/2)) + 'px';
		//return updated element
		return $(this).css({'margin-left':marginLeft, 'margin-top':marginTop});
	};

});

//close pop-up box
function closePopup()
{
	$('#opaco').toggleClass('hidden').removeAttr('style');
	$('#popup').toggleClass('hidden');
	return false;
}

//open pop-up
function showPopup(popup_type)
{
		//when IE - fade immediately
	if($.browser.msie)
		$('#opaco').height($(document).height()).toggleClass('hidden');
	else
		//in all the rest browsers - fade slowly
		$('#opaco').height($(document).height()).toggleClass('hidden');

	$('#popup')
	.html($('#popup_' + popup_type).html())
	.alignCenter()
	.toggleClass('hidden');
	
	setTimeout("closePopup()", 2000);
}