For interactive reports there is no problem, it works as desired.
For classic reports the important background colour in vita.css overrides my class when the mouse hovers the record. I tried setting the existing class to inherit, to find the same suggestion already for theme 24, but it doesn't solve the problem
I thought it would be nice to have a template option to disable row highlighting, since it's seems to be a common task. Turns out the option exists already under the classic report attributes and I initially missed it.