<!DOCTYPE html>

<html>
<head>
    <style>
        body {
            height: 2000px;
            background-image: linear-gradient(white, gray);
        }
    </style>
    <script>
        function scrolled()
        {
            if (parent && 'iframeScrolled' in parent)
                parent.iframeScrolled()
        }
    </script>
</head>
<body onscroll="scrolled()">
</body>
</html>