Properties Panel should have changeable background colours depending on the darkness you choose.
The properties panel, while handy, is annoyingly only one background colour; black text on a white background. I personally prefer to edit with dark panels and it makes the panel a real eye sore. It's overly bright compared the rest and it honestly makes it hard for me to focus sometimes (pedantic I know).
The darkness of your panels should dictate the background and text colours. So if I am using a darker panel setting the text of the properties panel should be darker with white text instead.