XY chart line.open area over the curve instead of under (keep-out zone)

I want to add a keep-out zone to a XY chart in perspective.
I need to have a colored area over and under my desired range.

It would be the opposite of this example from the documentation:

The bottom part is easy, I simply need to set the area color and opacity without choosing a line.open.y , however, I have not found a way to color the part at the top.

I would like to be able to keep the dynamic ranging of the axis because my data may have different orders of magnitude depending on user choices.

Thank you!