Weird, I had the same issue long time ago and made it work as mentioned before.
Can you provide an url to see it live? Its gonna be faster since I dont know how are you printing the catalogue list.
What I normally do is convert the catalogues into a menu, place the menu inside a div with an ID, and after style it as: (I havent been able to do this without JS using {module_catlist....} nor {tag_catlist...} )
#divID .selected a {}
#divID li.selected a {} also works
#u15567 li.selected a {
color: #ffacac;
}
Never seen that #u15567 before, shouldnt it look more like ul#nav_15567???