Change the Color of the Interface?

Open the Preferences dialog (Command-K [PC: Ctrl-K]) and click on Interface in the column on the left. At the top of the dialog you will be presented with four shades of gray (not 50 shades!), ranging from dark to light. Click on one to choose the interface Color Theme. There is also a checkbox that gives you the option to have the pasteboard match the interface theme color. Sadly, you can’t choose any other colors, but that might be a good thing!