Hi, Welcome to Sitepoint.
The first step in solving problems should always be to first check that you are using valid code.
As we see form your code you don't even have a doctype so IE will be working in quirks mode and using the broken box model among other bad things.
If you add a valid doctype then you can validate your page and pick up any errors and typos that have crept into the code. We can then immediately see that you have nested divs inside your anchors which is strictly not allowed as anchors are inline elements and can only contain other inline elements. You need to put the anchors inside the divs and not the other way around.
That menu should be a list anyway and not non-semantic divs. Always try to use the correct html element for the job in hand.
The css for the menu is duplicating a lot of styles and you don't need to do it that way. Set all the styles in one go and then just add the differences via the ID you are using. Therefore all you need to add is the width and the background-image. This will save tons of code.
Once we have fixed the html errors it seems that the problem has gone away.
Code:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />
<title>Untitled Document</title>
<style type="text/css">
/*--------------------------------------------------------------------------------------
Global
-------------------------------------------------------------------------------------- */
body {
margin:0;
font-family:Arial;
font-size:11px;
}
a img {
border:none;
}
div .product-list-item {
padding:15px;
}
div .category-list-item {
padding:10px;
}
/*--------------------------------------------------------------------------------------
Header
-------------------------------------------------------------------------------------- */
#headerWrapper {
float:left;
width:800px;
height:95px;
}
#headerLeft {
float:left;
width:275px;
height:95px;
background:url(http://www.nkasolutions.com/sites/header/themes/myframesmaster/images/layout/logo.gif) top left no-repeat;
}
#headerRight {
float:right;
width:240px;
padding-top:39px;
}
.headerRightContent {
float:right;
margin:5px auto;
color:#494949;
text-align:right;
}
/*--------------------------------------------------------------------------------------
Navigation
-------------------------------------------------------------------------------------- */
ul#navWrapper {
float:left;
width:800px;
height:33px;
font-size:0px;
list-style:none;
margin:0;
padding:0
}
ul#navWrapper li{
float:left;
height:33px;
text-indent:-8000px;
overflow:hidden;
}
ul#navWrapper a{
display:block;
height:33px;
}
#nav01 {
width:53px;
background:url(http://www.nkasolutions.com/sites/header/themes/myframesmaster/images/layout/nav01.gif) top left no-repeat;
}
#nav02 {
width:64px;
background:url(http://www.nkasolutions.com/sites/header/themes/myframesmaster/images/layout/nav02.gif) top left no-repeat;
}
#nav03 {
width:67px;
background:url(http://www.nkasolutions.com/sites/header/themes/myframesmaster/images/layout/nav03.gif) top left no-repeat;
}
#nav04 {
width:58px;
background:url(http://www.nkasolutions.com/sites/header/themes/myframesmaster/images/layout/nav04.gif) top left no-repeat;
}
#nav05 {
width:108px;
background:url(http://www.nkasolutions.com/sites/header/themes/myframesmaster/images/layout/nav05.gif) top left no-repeat;
}
#nav06 {
width:80px;
background:url(http://www.nkasolutions.com/sites/header/themes/myframesmaster/images/layout/nav06.gif) top left no-repeat;
}
#nav07 {
width:83px;
background:url(http://www.nkasolutions.com/sites/header/themes/myframesmaster/images/layout/nav07.gif) top left no-repeat;
}
#nav08 {
width:287px;
padding-top:9px;
background:url(http://www.nkasolutions.com/sites/header/themes/myframesmaster/images/layout/nav08.gif) top left no-repeat;
font-size:11px;
color:#FFFFFF;
text-align:right;
}
/*--------------------------------------------------------------------------------------
Left Column
-------------------------------------------------------------------------------------- */
td #ctl00_leftColumn.page-column-left {
vertical-align:top;
}
ul.module-list li {
list-style:none;
margin-left:-25px;
padding:0px 0px;
}
td .mod-body-body {
padding-top:10px;
padding-bottom:10px;
padding-right:12px;
}
td .mod-body-body input {
margin-left:17px;
font-family:Arial;
font-size:10px;
}
td .mod-body-body img {
width:18px;
height:12px;
}
/*--------------------------------------------------------------------------------------
Main Content Area
-------------------------------------------------------------------------------------- */
table {
clear:left;
}
tr.content-head-row td, tr.content-nav-row td {
text-align:center;
}
td #ctl00_centerColumn.page-column-center {
vertical-align:top;
/* padding:10px; */
}
td {
vertical-align:top;
}
.spacer20pixels {
clear: left;
width: 600px;
height: 20px;
}
.spacer1pixel {
clear: left;
width: 600px;
height: 1px;
}
#welcomeBar {
float:left;
width:607px;
height:26px;
background:url(http://www.nkasolutions.com/sites/header/themes/myframesmaster/images/layout/welcome_bar.gif) bottom center no-repeat;
}
#banner {
float:left;
width:607px;
height:180px;
background:url(http://www.nkasolutions.com/sites/header/themes/myframesmaster/images/layout/banner.jpg) bottom center no-repeat;
}
/*--------------------------------------------------------------------------------------
Footer
-------------------------------------------------------------------------------------- */
#belowFooterWrapper {
float:left;
width:800px;
height:30px;
margin:0 auto;
padding-top:5px;
color:#494949;
}
#belowFooterLeft {
float:left;
margin-left:7px;
}
#belowFooterRight {
float:right;
margin-right:7px;
}
#trademarkWrapper {
clear:left;
width:800px;
text-align:center;
}
a.navLink:link, a.navLink:active, a.navLink:visited, a.navLink:hover {
color:#FFFFFF;
font-family:Arial, Helvetica, sans-serif;
font-size:11px;
text-decoration:none;
}
a.grayLink:link, a.grayLink:active, a.grayLink:visited, a.grayLink:hover {
color:#494949;
font-family:Arial, Helvetica, sans-serif;
font-size:11px;
text-decoration:none;
}
</style>
</head>
<body>
<div id="headerWrapper">
<div id="headerLeft"> </div>
<div id="headerRight">
<div class="headerRightContent"> <a href="login.aspx">Sign in</a> | <a href="cart.aspx">View Cart</a> | <a href="checkout.aspx">Checkout</a></div>
<form id="form1" method="post" action="">
<div class="headerRightContent">
<label for="searchtxt">Search</label>
<input id="searchtxt" name="searchtxt" type="text" />
<input type="image" src="http://www.nkasolutions.com/sites/header/themes/myframesmaster/images/buttons/custom_search_submit.gif" name="go"/>
</div>
</form>
</div>
</div>
<ul id="navWrapper">
<li id="nav01"><a href="index.aspx">Home</a></li>
<li id="nav02"><a href="products.aspx">Products</a> </li>
<li id="nav03"><a href="about-us.aspx">About Us</a></li>
<li id="nav04"><a href="policies.aspx">Policies</a></li>
<li id="nav05"><a href="newsandevents.aspx">News and Events </a></li>
<li id="nav06"> <a href="frameshop.aspx">Frame Shop</a></li>
<li id="nav07"><a href="tipsandfaqs.aspx">Tips & FAQs</a></li>
<li id="nav08">Questions? (800) 241-3196 M-F 10am-5pm PST </li>
</ul>
</body>
</html>
I'm not sure why you are using images for the navigation when the images look just like a text equivalent anyway., This seems really strange to me as you should simply be using text which is much more accessible.
Hope that helps
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