var modalStatus = 0;

function loadPopupModal(){
	if(modalStatus==0){
		$(".modal-background").css({
			"opacity": "0.5"
		});
		$(".modal-window").fadeIn("fast");
		$(".modal-background").fadeIn("fast");
		modalStatus = 1;
	}
}

function disablePopupModal(){
	if(modalStatus==1){
		$(".modal-background").fadeOut("fast");
		$(".modal-window").fadeOut("fast");
		modalStatus = 0;
	}
}

function centerModal(){
	var windowWidth = document.documentElement.clientWidth;
	var windowHeight = document.documentElement.clientHeight;
	var modalHeight = $(".modal-window").height();
	var modalWidth = $(".modal-window").width();
	$(".modal-window").css({
		"position": "absolute",
		"top": windowHeight/2-modalHeight/2,
		"left": windowWidth/2-modalWidth/2-12
	});
	//only need force for IE6
	
	$(".modal-background").css({
		"height": windowHeight
	});
	
}

$(document).ready(function(){
	
	$("#button").click(function(){
		centerModal();
		loadPopupModal();
	});
				
	$(".modal-close").click(function(){
		disablePopupModal();
	});
	$(".modal-background").click(function(){
		disablePopupModal();
	});
	
	$(document).keypress(function(e){
		if(e.keyCode==27 && modalStatus==1){
			disablePopupModal();
		}
	});

});