Yeah that's another funny one, you can go IFR at night if you're current for IFR (duh) but in "being current" there is no night requirement.
3 t/o and landings is for your LICENCE, and only applies if others are on board with you...
Currency for NVFR has a certain amount/type of night required...
To fly NVFR with the authority of IFR rating requires recency which is at least equal to that of NVFR.
So, if you're not current for NVFR, then no NVFR regardless of your IFR currency status.
If you are current IFR, you can fly at night, regardless of how much night you've flown in the past month/year/decade. But you've got to be in an IFR machine, complying with the IFR, and if it's not going to be just you on board (plus maybe your freight of choice), you've got to have your 3 ups/downs in 90 days.
Hows that?
CR