With a sub-theme, sometimes you need to remove some base-theme's stylesheets so it's easier to theme within your sub-theme. In that case, we can use the
libraries-override function, new in Drupal 8. You'd add this to your theme's
theme.info.yml file. In the example below, we are using core's
classy theme as a base-theme.
# Basic theme info. name: Dolphinea desciption: A Drupal 8 theme type: theme base theme: classy core: 8.x version: VERSION screenshot: screenshot.png # Remove unneeded stylesheets. libraries-override: classy/base: css: component: css/components/textarea.css: false css/components/menu.css: false css/components/item-list.css: false css/components/links.css: false css/components/form.css: false css/components/pager.css: false
Of note here is
classy/base > css > components. That follows the theme path from within Classy, i.e.