You need to link to the chromestyle.css and the chrome.js to get it working.
See the documentation here
and look at the demo here
Below is the sourcecode of the demo, I have highlighted the links that are missing on your page:
Code:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en">
<head>
<title>Chrome CSS Drop Down Menu</title>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />
<link rel="stylesheet" type="text/css" href="chrometheme/chromestyle.css" />
<script type="text/javascript" src="chromejs/chrome.js">
/***********************************************
* Chrome CSS Drop Down Menu- (c) Dynamic Drive DHTML code library (www.dynamicdrive.com)
* This notice MUST stay intact for legal use
* Visit Dynamic Drive at http://www.dynamicdrive.com/ for full source code
***********************************************/
</script>
</head>
<body>
<div class="chromestyle" id="chromemenu">
<ul>
<li><a href="http://www.dynamicdrive.com">Home</a></li>
<li><a href="#" rel="dropmenu1">Resources</a></li>
<li><a href="#" rel="dropmenu2">News</a></li>
<li><a href="#" rel="dropmenu3">Search</a></li>
</ul>
</div>
<!--1st drop down menu -->
<div id="dropmenu1" class="dropmenudiv">
<a href="http://www.dynamicdrive.com/">Dynamic Drive</a>
<a href="http://www.cssdrive.com">CSS Drive</a>
<a href="http://www.javascriptkit.com">JavaScript Kit</a>
<a href="http://www.codingforums.com">Coding Forums</a>
<a href="http://www.javascriptkit.com/jsref/">JavaScript Reference</a>
</div>
<!--2nd drop down menu -->
<div id="dropmenu2" class="dropmenudiv" style="width: 150px;">
<a href="http://www.cnn.com/">CNN</a>
<a href="http://www.msnbc.com">MSNBC</a>
<a href="http://news.bbc.co.uk">BBC News</a>
</div>
<!--3rd drop down menu -->
<div id="dropmenu3" class="dropmenudiv" style="width: 150px;">
<a href="http://www.google.com/">Google</a>
<a href="http://www.yahoo.com">Yahoo</a>
<a href="http://www.msn.com">MSN</a>
</div>
<script type="text/javascript">
cssdropdown.startchrome("chromemenu")
</script>
<form>
<p>Sample form to demonstrate hover over windowed objects in IE5.5 to IE6 via iframe shim technique. IE7+ not affected by issue.</p>
<select style="width: 80%">
<option>whatever</option>
<option>whatever</option>
<option>whatever</option>
</select><br />
</form>
<p><b>Note:</b> To see how the menu looks with an alternate theme, just change the code:</p>
<pre><link rel="stylesheet" type="text/css" href="chrometheme/chromestyle.css" /></pre>
<p>inside the HEAD section above to reference one of the three alternate CSS files instead: "chromestyle2.css", "chromestyle3.css", or "chromestyle4.css"</p>
<p><b>Version Note:</b> v2.4. Visit <a href="http://www.dynamicdrive.com/dynamicindex1/chrome/index.htm">http://www.dynamicdrive.com/dynamicindex1/chrome/index.htm</a> for instructions/ changelog.</p>
<p align="center">Copyright 2006-2008 <a href="http://www.dynamicdrive.com/notice.htm">Dynamic Drive</a></p>
</body>
</html>
you would want to remember the copyright notice as well.
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