Hi @giandigi,
Thank you for buying our theme. We hope it will meet all your expectations!
This is standard behavior with WordPress, I’m afraid.
As this is not breaking the page, changing this is considered customization work. Unfortunately, this is a service that we do not provide.
We only share snippet only to solve issues with our theme. Any further request for CSS snippets will have to be part of a defect that needs to be fixed urgently. No snippets will be shared otherwise.
Maybe this article might help you find the best plugin that suit your needs.
https://www.wpbeginner.com/plugins/5-best-related-posts-plugins-for-wordpress/
Best,