<html><head><title>White-Black</title></head>
<script>
function changeBodyColor(color) {
color -= 16;
if(color >> 4) {
document.body.style.background = "#" + color.toString(16) + "0000";
setTimeout("changeBodyColor(" + color + ")", 128);
}
}
</script>
<body style='background: red' onload='setTimeout("changeBodyColor(256)", 5000)'>
</body>