Base themes

Base themes are a starting point for your custom theme. Your theme will inherit templates, libraries and hooks implemented by the base.

Configure Base Theme

Add the base theme to your THEME.info.yml file.

base theme: classy

No Base Theme

Start from scratch. Drupal will use templates and libraries defined by modules.

base theme: false

Classy, Stable, Stable9

Drupal includes themes in core/themes. These may be used for now, but there is discussion on removing these in the future.