.chromestyle {
width: 99%;
font-weight: bold;
}

.chromestyle:after { /*Add margin between menu and rest of content in Firefox*/
content: "."; 
display: block; 
height: 0; 
clear: both; 
visibility: hidden;
}

.chromestyle ul {
border: 1px solid #BBB;
width: 100%;
background: url(chromebg.gif) center center repeat-x; /*THEME CHANGE HERE*/
padding: 4px 0;
margin: 0;
text-align: center; /*set value to "left", "center", or "right"*/
}

.chromestyle ul li {
display: inline;
}

.chromestyle ul li a {
color: #494949;
padding: 4px 7px;
margin: 0;
text-decoration: none;
border-right: 1px solid #DADADA;
}

.chromestyle ul li a:hover {
background: url(chromebg-over.gif) center center repeat-x; /*THEME CHANGE HERE*/
}

.chromestyle ul li a[rel]:after { /*HTML to indicate drop down link*/
content: " v";
/*content: " " url(downimage.gif); /*uncomment this line to use an image instead*/
}


/* ######### Style for Drop Down Menu ######### */

.dropmenudiv{
position:absolute;
top: 0;
border: 1px solid #BBB; /*THEME CHANGE HERE*/
border-bottom-width: 0;
font:normal 12px Verdana;
line-height:18px;
z-index:100;
background-color: white;
width: 200px;
visibility: hidden;
filter: progid:DXImageTransform.Microsoft.Shadow(color=#CACACA,direction=135,strength=4); /*Add Shadow in IE. Remove if desired*/
}


.dropmenudiv a{
width: auto;
display: block;
text-indent: 3px;
border-bottom: 1px solid #BBB; /*THEME CHANGE HERE*/
padding: 2px 0;
text-decoration: none;
font-weight: bold;
color: black;
}

* html .dropmenudiv a{ /*IE only hack*/
width: 100%;
}

.dropmenudiv a:hover{ /*THEME CHANGE HERE*/
background-color: #F0F0F0;
}

.dropdown ul {
	margin: 0;
	padding: 0;
	list-style: none;
	width: 150px;
	}
.dropdown ul li {
	position: relative;
	}
.dropdown li ul {
	position: absolute;
	left: 149px;
	top: 0;
	display: none;
	}
.dropdown ul li a {
	display: block;
	text-decoration: none;
	color: #777;
	background: #fff;
	padding: 5px;
	border: 1px solid #ccc;
	border-bottom: 0;
	}
/* Fix IE. Hide from IE Mac \*/
* html ul li { float: left; }
* html ul li a { height: 1%; }
/* End */
.dropdown ul {
	margin: 0;
	padding: 0;
	list-style: none;
	width: 150px;
	border-bottom: 1px solid #ccc;
	}
.dropdown li:hover ul { display: block; }
.dropdown li:hover ul, li.over ul { 
	display: block; }
	<ul id="nav">