1 - jó napot can also be translated as "good morning" 2 - László should be accepted, not only Leslie(?)

Can't it be "good day" as well?

I think "good day" is fine; we say that in English, and Hungarian doesn't differentiate between morning and afternoon after about 9am.

There is no specific time of day here. It could be morning or afternoon. The answer should also be correct as "good day".

Good morning or good afternoon? hmmmm

Say, isn't that the famous mathematician, Leslie Stablehand?