.topnav ul.mainnav{ 
	display: block; 
	position: absolute; 
	margin: 10px 0px 0px 500px; 
	padding: 0px 0px 0px 0px; 
	width: 600px;
	height: 25px; 
	list-style: none;
	float: left;
	}

.topnav ul.mainnav li{ 
	float:left;
	display: block; 
	margin:0; 
	padding:0; 
	list-style-type: none;
	}

.topnav ul.mainnav li a{ 
	display:block;
	padding: 3px 0px 0px 0px;
	height: 22px;
	width: 150px;
	font-weight:bold;
	text-align:center;
	color: #FFFFFF;
	text-decoration:none;
	background-image: url(../images/mainnav_bg.jpg);
	}
	
.topnav ul.mainnav li a:hover{
	text-decoration: underline;
}