# Customize

Rebilly Instruments can be customized in different ways from simple tweaks to the `theme` object to a fully controlled style using the `css` option, or by combining both.
Making sure the look and feel match your branding.

Rebilly Instruments is fully localized from placeholders to error messages and more.
Override the existing localizations or add your own language if is not supported.

Style
Customize the appearance and branding of payment forms.

Localize
Configure localization settings, translations, and multi-language support.

Layout
Customize the layout of payment forms.

CSS reference
CSS and styling options for the Rebilly Instruments library.