Customize form style with CSS (not for published forms)

Customize form style with CSS (not for published forms)

I am using Zoho Creator to run a Word Order database application and would like to know if it's possible to customize the layout of the form. I keep reading that you can customize a published from but that's not what I am looking for.

I know you can go to Settings > Customize but this only allows me to choose from pre-built layouts. 

The other thing I discovered is the option to set the form to single or double column in the screen where you can edit the form but this also is limited.

I would like to customize the layout further with CSS. Is this possible?