04 — Customization · Overview

Two layers of polish.

FormPing customization works in two layers. Themes control how the whole form looks. Custom CSS lets you override anything on a per-field basis.

Layer 1 — Themes (form-wide)

Themes live in the Form Builder's Design tab. Every value maps to a CSS variable on the rendered widget, so you can preview live and you don't need to write any CSS yourself.

See Themes for the full variable list.

Layer 2 — Custom CSS (per field)

Each field has a Style tab where you can paste arbitrary CSS. The rules are scoped to that single field at runtime, so you can target individual inputs without touching the rest of the form.

See Custom CSS for the allow/deny list and examples.

Field-specific style options

Some field types expose extra style controls in their Style tab — no CSS required:

Radio — button group, classic radio circles, or pill selector
Select — native dropdown or styled custom dropdown
Date — minimal picker, advanced picker, or native browser picker (see Date Picker)
Number — plain input or stepper buttons

Use themes for everything that should be consistent across the form, then reach for Custom CSS only for one-off effects. It keeps your forms maintainable.