"You're welcome, Maha."
Translation:عَفْواً يا مَها.
Actually here were two good answers, though both meaning different things. عَفْواً يا مَها. You are welcome. In the sense of 'my pleasure' أهلا يا مَها You are welcome, Maha. in the sense of 'Please do come in / Nice to see you'
In Lebanon, we also use عَفْواً to say "excuse me" if someone is in the way for example and you're trying to get through the crowd.
"You're welcome" is the answer to "thank you" in English, that is what 3afwan means here.
The way I was taught, the nunation diacritic goes on the letter before the final alif, not on the alif itself. So عفوًا.
And for those wondering, in Arabic, the final -un and -in, which express the nominative and genitive cases, respectively, are only written as diacritics, but -an, the accusative marker, actually changes the spelling of the word by adding a final alif. That is because, at the end of an utterance, you wouldn't pronounce the -un or -in at all, but would replace the -an with a long -aa sound. At least in Standard Arabic. The set expressions like shukran and 3afwan are always pronounced with a final -an in the vernaculars, even at the end of an utterance. Nobody would ever say "shukraa" in day-to-day speech.