Hey @Medea Bindewald2! I hear you; this is a great feature request.
In the meantime, it is possible to target those fields with custom CSS if that's something you're interested in. You can get to the Custom CSS box by clicking the magic wand icon from the toolbar on the righthand side of the form editor, then locate the box labeled 'Custom CSS'. Here's the code:
You can also change the error message styling if you want, with this code:
Of course, replace the hex codes with your own desired colours! :)
Oh, and to test out the error styling (if you chose to add that), just try to submit something invalid in the email field (like your name).