An Error Was Encountered

Error Number: 1054

Unknown column 'vdg.css' in 'where clause'

SELECT DISTINCT * FROM (`mod_directory_categories_lookup`) JOIN `mod_sub_categories_lookup` ON mod_directory_categories_lookup.bus_id = mod_sub_categories_lookup.bus_id JOIN `mod_directory` ON mod_directory_categories_lookup.bus_id = mod_directory.id WHERE `site_id` = 124 AND live = 1 AND mod_id = 27 AND mod_directory_categories_lookup.cat_id = 23 AND mod_sub_categories_lookup.cat_id = 23 AND mod_sub_categories_lookup.sub_cat_id = vdg.css ORDER BY `company` asc