Category as class

Hi there again.
Let’s say I got two categories: “cat-a” and “cat-b”.
I want to get all posts from the categories, that’s not a problem, but add a “style” to title link deppending of each post category:

<a class= cat-a> Title uno </a>
<a class= cat-b> Title dos </a>
<a class= cat-b> Title tres </a>
<a class= cat-a> Title cuatro [/a]

and so on…

How in template or shortcode can I do that?
Thanks in adcanve again!

https://www.ads-software.com/plugins/list-category-posts/