html, body, #container {

    width: 100%;

    height: 100%;

    margin: 0;

    padding: 0;

}

var stage = acgraph.create('container');

​

var black = '2 #000000 0.9';

var blue = '1 #2196F3 0.9';

​

// Creates pattern.

var pattern = stage.pattern(new acgraph.math.Rect(0, 0, stage.width(), stage.height()));

​

var circles = {

    cx: stage.width() / 2,

    cy: stage.height() / 2,

    step: 5

};

​

var max_circle_radius = Math.max(stage.width(), stage.height()) / 2;

for (var i = 0; i < max_circle_radius; i++) {

    pattern.circle(circles.cx, circles.cy, circles.step * i).fill('none').stroke(blue);

}

​

var firstRect = stage.rect(40, 25, 200, 100);

firstRect.fill(pattern);

firstRect.stroke(black);

​

var secondRect = stage.rect(2, 2, 50, 50);

secondRect.fill(pattern);

secondRect.stroke(black);