[horde] Add custom CSS doesn't work.

[Briongos Caballero, Sergio]

Hi, I have installed Horde Groupware Webmail Edition 5.2.1. and I need add custom css.

I created a new css file: mycss.css and created config/hooks.php with:

    public function cssfiles($theme)
    {
        return array(
              '/var/www/horde/customCSS/mycss.css' => '/horde/customCSS /mycss.css'
        );
    }

mycss.css contents:

#horde-version {
        visibility: hidden;
}

But horde is not loading this new css file.

Thanks in advance.