spotlessly       
adverb uk/ˈspɒt.ləs.li/ us/ˈspɑːt.ləs.li/
 一尘不染地;极清洁地
in an extremely clean way
  The kitchen is spotlessly clean. 厨房一尘不染。 
 The bedrooms in the hotel are spotlessly kept. 这家旅馆的房间打扫得一尘不染。 
 See: spotless
 - More examples
 - He passed me a spotlessly fresh handkerchief.
 - She cleans up spotlessly after she has finished cooking.
 - He was working in his spotlessly tidy office.