<!DOCTYPE html>
<html>
<head>
    <title>CSS Filter Test: Test for Saturate short hand</title>
    <style type="text/css">
    div {
        width: 500px;
        height: 500px; 
        background: rgb(255, 0, 0);
        filter: contrast(100%);
        position: absolute;
    }

    </style>
</head>
<body>
    <p>You should see a gray rectangle.</p>
    <div></div>

</body>
</html>