Add this code to the Custom CSS field on the Appearance tab of your FAQ widget’s settings:
/* FAQ title font and size */
.eui-widget-title{
font-size: 24px !important;
}
/* FAQ category title font and size */
.eapps-faq-content-category-title-text{
font-size: 22px !important;
}
/* FAQ question font and size */
.eapps-faq-content-category-item-question{
font-size: 18px !important;
}
/* FAQ answer font and size */
.eapps-faq-content-category-item-answer-text{
font-size: 18px !important;
}