Hello
If you want to remove the text-gradient class, you can edit this file:
root/templates/ja_trip/html/layouts/chromes/t4section.php
Look for this line of code:
$modTitle = '<'.$headerTag.' class="section-title h3 text-gradient'.$headerClass.'" data-aos="fade-up"><span>'.$module->title.'</span></'.$headerTag.'>';
and remove this class there.
and add this custom CSS rule to override the color:
.section-title-wrap .section-title {
color: /*your_desired_color_here*/;
}