I am using the below css code to block the entire page when the popup appeared. But it's working(The visible page only covered not all). I have a problem, if my page having a scroll bar means the remaining bottom of the page not covered by the blocker.
.parentDisable
{
z-index: 99999;
width: 100%;
height: 100%;
display: none;
position: absolute;
top: 0%;
left: 0%;
background-color: #000;
color: #aaa;
opacity: 0.8;
filter: alpha(opacity=100);
}
#popup
{
width: 300;
height: 300;
position: relative;
color: #000;
top: 25%;
}