Zero values in bar chart still showing, and lines between them

[thany]

My goal is to create a chart that shows a background for one part of the data, and no background for another part of the data. It's a line graph, and I was thinking to fake the alternating background using bars. So that becomes a multiChart.

For the bar values, I'm alternating between 0 and 100. So a value of 100 will show some background, and 0 will not.

Here's the problem:

1) A bar that has a value of 0 on the Y-axis, will still show one pixel. I would expect it not to be drawn at all. Zero means nothing, nada, nil. Not "a very slight amount that renders as 1 pixel". 2) There's an arbitrary amount of space between all bars, that so happens to be a pixel. How do I tell the graph to glue bars together?

See: The flat little lines are bars that are supposed to be 0. So 0 in height, so I shouldn't see anything there, The white lines between the bars I want to get rid of.

How can I do this?

[thany]

Ok, so if I add this into the chart options:

bars2: {
  groupSpacing: 0
}

The lines between bars get thinner, but still not zero.

Also, why are they not black? I specify them to be black and they are dark grey?... Wut?