<!DOCTYPE html>
<html>
<body>
<script>

var canvas = document.createElement('canvas');
canvas.width = 500;
canvas.height = 500;
canvas.style.width = '100px';
canvas.style.height = '100px';
var ctx = canvas.getContext('2d');

ctx.filter = 'drop-shadow(0 50px black)';
ctx.fillStyle = '#0f0';
ctx.fillRect(125, 125, 250, 200);

document.body.appendChild(canvas);

</script>
</body>
</html>
