This is what you want:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0//EN">
<title>Javascript test</title>
<style type="text/css">
div{width:10em;height:10em;background:#000;color:#fff}
</style>
<script type="text/javascript">
window.onload = function(){
div = document.getElementsByTagName('div')[0];
div.onmouseover = function(){
div.style.backgroundColor = '#fff';
div.style.color = '#000';
}
}
</script>
<div>
<p>That <code>div</code> element.
</div>
Or at least, something like this.
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