Disable styles completely
Image Choices (> 1.3.10) includes a filter you can add to your theme to totally disable Image Choices styles completely. With this filter added, you’ll need to add your own custom CSS to style the layouts and styles of all your image choice fields.
NOTE: This filter is for legacy versions (< 1.4) or new version where Legacy Mode is enabled
Just add the following to your theme functions and the default CSS will not be enqueued.
add_filter( ‘gfic_enqueue_core_css’, ‘__return_false’ );