A Bar chart with a rotating background on dual canvas tags

This is the dual canvas version of this demo that uses two canvas tags. The background rotates on the rear canvas and the Bar chart is drawn on the foreground canvas. The single canvas version can be found here .

[No canvas support] [No canvas support]

This goes in the documents header:
<script src="RGraph.common.core.js"></script>
<script src="RGraph.common.dynamic.js"></script>
<script src="RGraph.common.tooltips.js"></script>
<script src="RGraph.bar.js"></script>
Put this where you want the chart to show up:
<div style="position: relative; display: inline-block; width: 750px; height: 250px">
    <canvas id="cvs_background" width="750" height="250" style="position: absolute; top: 0; left: 0">[No canvas support]</canvas>
    <canvas id="cvs_foreground" width="750" height="250" style="position: absolute; top: 0; left: 0">[No canvas support]</canvas>
</div>
This is the code that generates the chart: