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<canvas width="600" height="400"></canvas>
<script >
var pantalla = document.querySelector("canvas");
var pincel = pantalla.getContext('2d');
pincel.fillStyle = "lightgrey";
pincel.fillRect(0,0,600,400);
pincel.fillStyle = "darkgreen";
pincel.fillRect(125,50,350,300);
pincel.fillStyle = "black";
pincel.fillRect(175,100,90,90);
pincel.fillStyle = "black";
pincel.fillRect(335,100,90,90);
pincel.fillStyle = "black";
pincel.fillRect(265,190,70,100);
pincel.fillStyle = "black";
pincel.fillRect(225,240,40,110);
pincel.fillStyle = "black";
pincel.fillRect(335,240,40,110);
</script>
