you can add your own class under post loop item,
add_filter('post_grid_item_classes', 'post_grid_no_post_text_20200614', 10, 2); function post_grid_no_post_text_20200614( $item_css_class, $args){ $post_id = $args['post_id'] ; $item_css_class['custom-new'] = 'custom-class'; return $item_css_class; }
Include post terms slug
add_filter('post_grid_item_classes', 'post_grid_no_post_text_20200614', 10, 2); function post_grid_no_post_text_20200614( $item_css_class, $args){ $post_id = $args['post_id'] ; $item_css_class['post_term_slug'] = post_grid_term_slug_list($post_id); return $item_css_class; }