I've updated the main node, but am posting this just so that people may notice this thread being updated in RAT or NN.

I've changed my CSS to be:

tr.highlight, tr.NN-highlight {
  background-color: #eee;
}
[download]

This highlights everything lightly, the way I like it. Feel free to steal/modify to your liking. If you want no highlighting, as a lot of people seem to, then you shouldn't need to do anything. Or you may want to remove what you did do.

I did not opt for a user setting on this. After looking at the theme code which is spread out over a few locations, and noticing demerphq's thoughts on PM CSS, I'm hoping to ride his coattails on that process instead. I agree with that node - we need to come up with something a bit simpler to use, with a lot more consistency to allow themes to work easily. No point in me going and trying to come up with something that needs to be reworked later anyway.