In his response to your question, the prominent Muslim scholar, Sheikh Muhammad Iqbal Nadvi, Director and Imam of Al-Falah Islamic Center, Oakville, Ontario, Canada, states:

“Generally speaking, you are allowed to color your hair except black. But if your husband does not agree with it, then it is for the best interest of mutual agreement in the house that you refrain from doing it until you convince him. But generally there is nothing wrong with dying or highlighting your hair.