Hey Santi,

I am not encourage you modify the core file for this custom styling purpose is because when you update to another new version, it will overwrite your custom style file to original.

Perhaps you can try apply this following css code in your current template css file and see how it goes?

div#fd.eb .eb-navbar-nav > li > a {

    background: #eee !important;

}



div#fd.eb .eb-navbar-nav > li > a {

    color: #666666;

}