B. On A the burger sits on flat black, so the photo and the UI stay two layers. On B the smoky green wraps the photo and the fields, and the screen reads as one light. The orange Sign In still has a place to land.

Keep the orange as the only hot color when you wrap the screens in the green. If the fields, the photo, and the button all go smoky, the Sign In loses the place it had on B. The green should be the room. The orange stays the action.