Hi Saguaros! Looking a little deeper into this issue, I figured out that I just need some further help from you to assist me. I need to find a way in the template to set CSS Classes on the action buttons within each article (like "Read More") so we can define specific articles where to raise a popup trigger a specific custom CSS Class. Best regards!
The current section you're referring to belongs to Articles Category module, this file renders elements of articles:
/templates/ja_flix/html/mod_articles_category/news-1.php
Kindly check.