Marking lines on the straw mat of a Masjid to define rows

Q 11: What is the ruling on drawing a slanted line on carpets or mats in a Masjid (mosque) facing the Qiblah (Ka`bah-direction faced in Prayer) to organize the rows?

A: There is no harm in doing so, and there is also no harm if people perform Salah (Prayer) with no line, because a little deviation from the direction of Qiblah has no significant effect.May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.