> before item

Hello,

I use your plug-in into a mega menu, and I need to mark each line with a special char like ‘> ‘

I try this css

#mega-menu-wrap-primary #mega-menu-primary li li li:before{
content:">  ";
display: inline-block;
margin-left: -15px;
width: 15px;
height: 8px;
}

but it doesn’t works.

Could you help me ?
Here is the link for the website I use the plug-in
http://www.carolinescherb.com/wp/

carosch

https://ww.wp.xz.cn/plugins/list-category-posts/