var x = document.getElementById("myCanvas");
var y = x.getContext("2d");

function fillSquare(w, h, s) {
  y.fillRect(w, h, 300, s);
}

y.fillStyle = "#1e8214";
fillSquare(10, 10, 425);
fillSquare(390, 10, 425);
y.fillStyle = "#ffe094";
fillSquare(200, 10, 425);

y.strokeStyle = "#ffe094";
y.lineWidth = 5;
y.moveTo(0, 0);
y.lineTo(0, 130);
y.stroke();