<!DOCTYPE html>
<html>
<head>
<style>
input[type="text"]:enabled
{
background:#ffff00;
}
input[type="text"]:disabled
{
background:#dddddd;
}
</style>
</head>
<body>
<form action="">
First name: <input type="text" value="Mickey" /><br>
Last name: <input type="text" value="Mouse" /><br>
Country: <input type="text" disabled="disabled" value="Disneyland" /><br>
</form>
</body>
</html>