Hi, I added a new short tutorial last week to our docs, feel free to check it out here.
It shows how to change the visual appearance of an input field depending what user has typed there. You can use Formulas to define the validation rules in any way you like (there’s few examples in the tutorial).
The tutorial should teach you how to utilize Formulas in style properties based on variable values. It also presents a way to use different events available for each input.