Customize recent blog posts carousel

Hello,
I want to customize the recent blog posts carousel on my homepage, but i can’t identify the files i need to.
I just want to add above the title of the blog post a label (with different colors) of the post category (Actu, Dossier or Portrait) and i need a litlle help.

This is the result i would like :

URL of the website : http://ims-entreprendre-test.geolane.fr/

Thanks a lot!
Best regards,
Ced

Ticket