[css] Font Awesome 5 font-family issue

I didn't want to use the 'all' version, so searched the 'fontawesome-all.min.css' file (previously included in the header) for 'family' tag and found at the end a declaration @font-face{font-family:**Font Awesome\ 5 Free**;font-style:normal;

So, in the stylesheet for an element where I wanted to use the content: "\f0c8"; code, I've added (or changed to) font-family: Font Awesome\ 5 Free; and it worked.

.frb input[type="checkbox"] ~ label:before {
    font-family: Font Awesome\ 5 Free;
    content: "\f0c8";
    font-weight: 900;
    position: absolute;
}