"The restaurant is dirty, but the food itself is not bad."
Translation:Restoran kirli ama yemeğin kendisi kötü değil.
I'm sorry to disagree... But noun compounds do not use genitive case ending on the first component. Examples include "hayvanat bahçesi" (NOT "hayvanatın bahçesi.") and havalimanı (NOT "havanın limanı.") More info in Tips & Notes: Time
Duo's sentence (and your other example) both use a genitive-possessive construction where the possessor is marked with
genitive case ending -(n)in and the possessed noun is marked with a
possessive suffix -(s)i. More info in Tips & Notes: Possessives
So this sentence literally translates as: "The restaurant is dirty but the food's self is not bad."