CiviCRM CSS outside of CiviCRM
Wrong question was asked; fancy CiviCRM stuff works almost, if properly called via CiviCRM own jQuery methods; pretty strange  CRM.alert in Chrome pops up a default JS alert() message though, so it might be better to use  CRM.status with appropriate parameters

This page helps a lot: https://wiki.civicrm.org/confluence/display/CRMDOC/Notifications+and+Confirmations 

Additional reading:


https://wiki.civicrm.org/confluence/display/CRMDOC43/Javascript+Reference
https://wiki.civicrm.org/confluence/display/CRMDOC43/Resource+Reference#ResourceReference-Javascript
https://wiki.civicrm.org/confluence/display/CRMDOC/Ajax+Pages+and+Forms#AjaxPagesandForms-CRM.refreshParent