Code:
<html>
<head>
<script language="javascript">
function l_over(id)
{
document.getElementById(id).style.backgroundColor = "ccccff";
}
function l_out(id)
{
document.getElementById(id).style.backgroundColor = "cccccc";
}
</script>
</head>
<body>
<table>
<tr id="1" style="background-color:#cccccc;" onmouseover="l_over(1)" onmouseout="l_out(1)">
<td></td>
</tr>
<tr id="1" style="background-color:#cccccc;" onmouseover="l_over(2)" onmouseout="l_out(2)">
<td></td>
</tr>
<tr id="1" style="background-color:#cccccc;" onmouseover="l_over(3)" onmouseout="l_out(3)">
<td></td>
</tr>
</table>
</body>
</html>