Is a Muslim woman required to pray in two garments (trousers and a top), or is it permissible for her to pray in one garment that covers her entire body?

A Muslim woman must cover her entire body during prayer, except for her face, as stated in the hadith: "Allah does not accept the prayer of a menstruating woman except with a head covering (khimar)." The covering must be ample and loose, not revealing the size of the body. A single garment that covers the body is sufficient. There is no specific dress code for a woman's prayer; the ruling is tied to modesty (ستر), so whenever modesty is achieved, the prayer is valid.