#nav {
	z-index:50;
	position:absolute;
	top:0;
	left:0;
	width:100%;
	height:100%;
	background:#000000;
	opacity: .4; filter: alpha(Opacity=40); -khtml-opacity: .4;
	display:none;
} 
#imagem{
	z-index:51;
	position:absolute;
	top:0;
	left:0;
	overflow:auto;
	width:100%;
	height:100%;
}
.legenda{
	color:#000000;
	font-family:Arial, Helvetica, sans-serif;
	font-size:11px;
}