#floatBannerFundo {
z-index:1001;
width:100%;
height:200%;
position: absolute;
top:0; 
left:0;
background-color:#000;
filter:alpha(opacity=80);
opacity: .8;
-moz-opacity: .8;
text-align:center;
}

#floatBanner {
z-index:1021;
width:100%;
position: absolute;
margin-top:100px;
text-align:center; 
}
#floatBanner .banner
width:400px;
margin-left:auto;
margin-right:auto;