My theme works for the "selection" and "header" card properties, but not for "cardTitle". I fyou can see in the screenshot to the right, what I want to control is the "Font color" and "Background color" for the "Title" section.
The problem is that I cannot find any corresponding json-name to use to control this. I have looked at the documentation and also tried to identify the card property group from the properties that should be there, given the appearance of the "Title" section but sadly I haven't been able to find any solution.
I also tried to reverse engineer the json-tag by looking at HTML from within Power BI Service. This is the div-tag containing the title for my slicer: