ljubazno

1. (of behaviour) kindly; politely
   Prodavačica nam je ljubazno objasnila kako da stignemo do stanice. — The shop assistant kindly explained how to get to the station.
   Ljubazno vas molimo da isključite mobilne telefone. — We kindly ask you to switch off your mobile phones.

In the thanking formula "to je ljubazno od vas/tebe", ljubazno is the neuter form of the adjective ljubazan, not the adverb.