HTML Image area maps

Here is a quick html that kind of shows HTML overlay with an image at the center and certain part of the image is clickable (such as X button and a launch button ). Below is the snippet that helped with this.

html, body, #wrapper {
   height:100%;
   width: 100%;
   margin: 0;
   padding: 0;
   border: 0;
   background-color:rgba(0,0,0,0.3)
}
#wrapper td {
   vertical-align: middle;
   text-align: center;
}

references:
http://www.position-relative.com/tutorials/tute1_css_bg_image.php