Ui template theme field must select, can't use none

Playing with ui-template and buttons. Trying different CSS combos and I wanted to totally control the look with out interference from node-red. Turns out that you must select a theme on the ui-page node or it tells you there is a configuration problem when you deploy. Is this right? Why have a NONE selection when you can't select none? Or you can select but the system yells at you. Even with my browser tools I'm having a rough time figuring out which fields are which so I can over ride in CSS.