Is it permissible for a Muslim woman to wear the correct hijab (khimar, or idna, or isdal, or milhafah) that is common in a particular place, with the intention that it is a fashion and in keeping with the general atmosphere of her environment, and not with the intention that it is an obligation enjoined by Allah and His Messenger?

The obligation of hijab (definition) is fulfilled by wearing it, even without intention, although intention is a condition for earning reward and recompense. Every act from which no immediate benefit is apparent, and whose purpose is to seek reward, requires intention. However, if its benefit is apparent and it is naturally practiced even before religious injunction, then intention is not required for it, except for those who intend another meaning by their action that entails reward. Thus, hijab achieves modesty and protects one from many sins that befall the immodest woman.