What is the ruling on studying and working in the field of interior design ("decoration")? Is it forbidden, especially since there is mixing (of genders) in study and work, and it has been mentioned that an abundance of ornamentation and showing off in buildings are among the signs of the Hour?

The questioner is congratulated on their repentance and their desire to uphold the religion. It is mentioned that decorating mosques is blameworthy, and there are authentic narrations that warn against it and consider it a sign of destruction. Among these is the hadith of Abu Darda: "If you decorate your mosques and adorn your Qur'ans, then destruction will be upon you." It is also narrated from Ibn Abbas that the Prophet, peace and blessings be upon him, said: "I was not commanded to erect lofty mosques," and that Ibn Abbas said: "You will surely decorate them as the Jews and Christians decorated [theirs]." The text also indicates that excessive building is among the signs of the Hour, as mentioned in the famous hadith of Gabriel. Regarding the architectural engineering specialization, the questioner is advised to leave it, as it is not suitable for women and is considered a field of ikhtilat (unrestricted mixing of genders). They are called upon to seek a specialization that suits a Muslim woman, or to abandon studies if there is no pressing need for them.