Is it lawful or unlawful for a woman (sister) to wear pastel colors or any other bright colors? And why is it lawful or unlawful? Provide proof and evidence from Qur'an and Sunnah, or from some scholarly knowledge!

Praise be to Allah, the Lord of the Worlds; and may His blessings and peace be upon our Prophet Muhammad and upon all his Family and Companions. There is no harm if a woman wears pastel colours or similar things if that does not cause a violation of any Islamic injunctions like preventing water from reaching the skin, for that would render the ablution invalid. Also they should not cause any harm nor should they be made of unclean ingredients. Allah knows best.