_color_shift($given, $ref1, $ref2, $target) Shifts a given color, using a reference pair and a target blend

color_help($route_name, RouteMatchInterface $route_match) Implements

template_preprocess_color_scheme_form(&$variables) Prepares variables for color scheme form templates.

color_block_view_pre_render(array $build) #pre_render callback: Sets color preset logo.