Is it permissible to marry civilly without the parents' knowledge due to their rejection of tribal differences, and is this marriage considered legitimate [in Islamic law]?

The majority of scholars stipulate the guardian (wali) as a condition for the validity of marriage, thereby differing from Abu Hanifa. Therefore, it is not permissible to proceed with a marriage without the woman's guardian according to the majority. If it occurs, it is invalid. However, if a Sharia judge rules it valid after the fact, it proceeds and is not annulled. We advise convincing the woman's guardian. If he insists on refusal and the wife is suitable (kufu'), she may refer the matter to the judge to marry her off or order her guardian to do so. A suitor should not be rejected merely due to a difference in tribe if he meets the criteria of religiosity and good character.