Change question color after clicking on it

Add this code to the Custom CSS field on the Appearance tab of your FAQ widget’s settings:

.eapps-faq-content-category-item-active .eapps-faq-content-category-item-question-text {
 color: red!important;
}
.eapps-faq-content-category-item-question-text {
   transition: all 0.5s ease;
}