Add this to your css file or inside your “head� tags:

.darkenBackground {
background-color: rgb(0, 0, 0);
opacity: 0.7; /* Safari, Opera */
-moz-opacity:0.70: /* FireFox */
filter: alpha(opacity=70); /* IE */
z-index: 20;
height: 100%;
width: 100%;
background-repeat:repeat;
position:fixed;
top: 0px;
left: 0px;
}


Basically, this says set a style in CSS to have a black background, 70% transparent, filling the entire screen.

We then add this code anywhere inside our “body� tag:

<div id=�darkBackgroundLayer� class=�darkenBackground�>
<script language=�javascript� type=�text/javascript�>
document.getElementsById(�darkBackgroundLayer�).style.display = “none�;
</script>


This places our black box on the screen, and then the javascript hides it. We can then show it later on by putting this javascript in an event handler like onclick:

document.getElementsById(�darkBackgroundLayer�).style.display = “�;