code: def focusout(self, event):
          
          bc = self.style.lookup("TEntry", "bordercolor", ("!focus",))
          dc = self.style.lookup("TEntry", "darkcolor", ("!focus",))
          lc = self.style.lookup("TEntry", "lightcolor", ("!focus",))
          self.style.configure("%s.spinbox.TFrame" % self.frame, bordercolor=bc,
                               darkcolor=dc, lightcolor=lc)
docs: Change style on focus out events.