<script>
var tela = document.querySelector('canvas');
var pincel = tela.getContext('2d');
pincel.fillStyle = 'darkgreen';
pincel.fillRect (0, 0, 350 ,300);
pincel.fillStyle = 'black';
pincel.fillRect (50, 50, 90 ,90);
pincel.fillStyle = 'black';
pincel.fillRect (210, 50, 90 ,90);
pincel.fillStyle = 'black';
pincel.fillRect (140, 140, 70 ,100);
pincel.fillStyle = 'black';
pincel.fillRect (100, 190, 40, 110);
pincel.fillStyle = 'black';
pincel.fillRect (210, 190, 40, 110);
</script>
