Down to it - Idioms by The Free Dictionary
down to (someone or something) (redirected from down to it)
down to (someone or something)
Including everyone or everything in a group or list. She's obsessing about every aspect of wedding planning, down to the shade of the ink on the invitations.
down to somebody/something even including the last item of a whole list of people or things: Everybody was affected by the economic crisis, from the president down to the poorest citizen. ♢ She’s thought of everything down to the tiniest details!