Try this css:
<html>
<head>
<title>Form</title>
<style>
.List {
BACKGROUND: lavender; FONT: 8pt verdana,arial,sans-serif
}
.Heading
{
color:navy;
background: #ffffcc;
}
</style>
</head>
<body bgcolor="#FFFFFF" text="#000000">
<form name="form1" method="post" action="">
<select name="select" class="Heading">
<option class="list">Option 1</option>
<option>Option 2</option>
<option>Option 3</option>
<option>Option 4</option>
<option>Option 5</option>
<option>Option 6</option>
</select>
</form>
</body>
</html>