gistfile1.txt

$tracks-total: 10;

%tracks-used {
    font-family: FontAwesome;
    content: "\f058";
    font-size: 23px;
}

.anw-account__demo__counters {
    color: $anw-brand-light-grey-4;
    
    @for $i from 0 through $tracks-total {
        &[data-tracks="#{$i}"] {
            li:nth-child(-n+#{$tracks-total - $i}) {
                color: $anw-brand-5;
                .fa:before {
                    @extend %tracks-used;
                }
            }
        }
    }
}