Block's Theme

A Block’s Theme is a CSS stylesheet that can be applied to any block. You can define multiple themes, but only one theme can be applied to a single block instance at a time.

The CSS contained in a theme does not remove or replace any existing CSS defined within the block. However, if a class is redefined in the theme, the theme’s definition will take precedence over the block’s original CSS.

In practical terms, applying a theme means that its CSS is appended after the block’s own CSS, ensuring that the theme’s styles override any matching rules defined earlier.

Please read CSS Priorities for learning CSS priorities works on the web builder