Conditional Formatting of Data Labels on Chart

Hi!

Please, help me.

I have very simple task: to show plan\actual chart and the result (see the picture below).

I can build combined chart and use the second axis to show the result: show only labels:

Labels marked with yellow color below

But the problem is that i need conditional formmating for data labels of result.

It is very simple: red color if value is below zero.

Please, help me.

Maybe there is custom visualisation, or some trick to build charts like that.

I believe, that my case is not super unique and  somebody trited to solve such case.

Thank you!