$(document).ready(function() {

//Put in the DIV id you want to display
launchWindow('#dialog2');

//if close button is clicked
$('.window .close').click(function (e) {
e.preventDefault();

$('#mask').hide();
$('.window').hide();
});

//if mask is clicked
$('#mask').click(function () {
$(this).hide();
$('.window').hide();
});
});


function launchWindow(id) {

//Get the screen height and width
var maskHeight = $(document).height();
var maskWidth = $(window).width();

//Set heigth and width to mask to fill up the whole screen
$('#mask').css({'width':maskWidth,'height':maskHeight});

//transition effect
$('#mask').fadeIn(1000);
$('#mask').fadeTo("slow",0.8);

//Get the window height and width
var winH = $(window).height();
var winW = $(window).width();

//Set the popup window to center
$(id).css('top', winH/2-$(id).height());
$(id).css('left', winW/2-$(id).width()/2);

//transition effect
$(id).fadeIn(2000);
}