Yup, that's a neat idea, thanks ;p.
----
OT:
nuit is a feminine noun, so the adjective
bon should inherit that gender

. Speaking of genders, we usually put the feminine nouns first in that kind of constructs (f.g., as in
Mesdemoiselles, messieurs when (relatively formally) addressing a room)

.
On the other hand, I'd as a native speaker tend not to distribute the different genders over the noun
ami in that instance, and when we do that, it's the masculine gender that wins. (Confused yet?

).
TL;DR:
Bonne nuit mes amis! (A more idiomatic phrasing would even switch the possessive for a generic deictic ->
Bonne nuit les amis!, but that's even more subtle to explain ^^).
Yes, French grammar is ghastly

. (And that took a few edits and a quick check in a dictionary to double-check something, so, err, don't despair if you're learning French? ^^).
(Take my terminology with a grain of salt, I'm not used to speaking about French grammar in English

).