Is it permissible for a woman who used to wear the khimar as an act of devotion, considering it not obligatory, to abandon it after performing Istikhara, and instead wear trousers with long blouses, claiming that God guided her to good after the Istikhara?

The Shari'ah has not specified a particular type of clothing for women, but scholars have set conditions for the legal hijab that must be met in one's attire. Istikhara (prayer for guidance) is not permissible in this matter, as it is specific to permissible matters and not to what is unlawful. Wearing trousers that reveal the size of the leg is not permissible.