عيد مبارك means Have a blessed Eid.
I sat with my housemates two nights ago during Iftar (إفطار). My housemates are a Somali man, a Pakistani man, and a Sudanese man. Our Chaldean (الكلدانيون) colleague cooked their meal for them. They are all quite nice. We talked about our home countries, foods, and, because I wouldn't let it go, one of the budgets for work.