Add Social Icon in top header

I add a “call us” Icon but It isn’t shown

I request an help only for that, I add code in function.php and custom css but I don’t see this icon. I’m wrong in something but don’t know where!

// Add new icon as an option for social icons
function avia_add_custom_social_icon($icons) {
$icons[‘Facebook’] = ‘facebook’;
$icons[‘Google Plus’] = ‘gplus’;
$icons[‘Twitter’] = ‘twitter’;
$icons[‘Instagram’] = ‘instagram’;
$icons[‘You Tube’] = ‘youtube’;
$icons[‘Skype’] = ‘skype’;
$icons[‘Italia’] = ‘italia’;
$icons[‘Uk’] = ‘uk’;
$icons[‘Call’] = ‘call’;
$icons[‘Mail’] = ‘mail’;
return $icons;
}
add_filter(‘avf_social_icons_options’,’avia_add_custom_social_icon’, 10, 1);

And in the custom css there’s this code for all the icon I added

#top #wrap_all .av-social-link-kriesi a:before{
content: “”;
width: 20px;
height: 20px;
display: inline-block;
vertical-align: middle;
background: url(……..) no-repeat center center;
background-size: contain;
}

Sorry for my bad english, I know is difficult to understand what I write.
I have to add in the top bar a phone/call icon linked to a linkable number of customer care of this site biesseracing.com
Enfold does not have phone icon, so I followed the tutorial guide http://kriesi.at/documentation/enfold/custom-social-icons/.

I added two kind if code:
in function.php —> function avia_add_custom_social_icon($icons)
{ $icons[‘Call’] = ‘call’;
return $icons;
}
add_filter(‘avf_social_icons_options’,’avia_add_custom_social_icon’, 10, 1);

in Option Theme-> custom code –>

#top #wrap_all .av-social-link-call a:before{
content: “”;
width: 20px;
height: 20px;
display: inline-block;
vertical-align: middle;
background: url(…url of the icon image…..) no-repeat center center;
background-size: contain;
}

After doing this, I move in the admin panel of theme and I would add “call” icon but there isn’t.
I would like to understand where I’m wrong and why I cannot see this icon.