Here is an SVG scrolling Line chart which has had three semi-opaque rectangles placed on top of the chart - one red, one yellow and one green.
This goes in the documents header:<script src="RGraph.svg.common.core.js"></script> <script src="RGraph.svg.line.js"></script>Put this where you want the chart to show up:
<div style="width: 600px; height: 250px; display: inline-block; background-color: black"></div>This is the code that generates the chart: