Префиксы для тем + возможность добавить Font Awesome 4 или своё изображение

[buran1715]

buran1715, так попробуй

.label{
    border-radius: 0px;
    display: inline-block;
    position: relative;
    cursor: pointer;
    font-weight: bold;
    min-width: 70px;  
    text-align: center;
    &:before{
        position: absolute;
        border-top-right-radius: 10px;
        border-right: 2px solid rgba(0,0,0,0.1);
        top: 0;
        bottom: 0;
        left: 0;
        padding: 1px 4px 0 3px;
        width: 20px;
        text-align: center;
    }

}

.addLabel(@name_nof, @color, @fa-uid:"none") when (iscolor(@color)){
    @name: e(%('label--%s', @name_nof));
    a.label.@{name}:hover, a:hover .label.@{name}{
        background-color: shade(@color, 4%) !important;
    }
    .@{name}{
        background-color: @color !important;
        border-color: shade(@color, 20%) !important;

        color: contrast(@color);
       
        &when (iskeyword(@fa-uid)){
            padding: 0 5px 0 32px;
            &:hover:before {
                background-color: rgba(0,0,0,0.3)!important;
            }
            &:before {
                background-color: rgba(0,0,0,0.2)!important;
                content: "\@{fa-uid}";
                .m-faBase();

            }
            &:after {
                content:  "";
                margin-left: -29px;
            }
        }
        &when (isurl(@fa-uid)){
            padding: 0 5px 0 32px;
            &:before {
                background-color: rgba(0,0,0,0.2)!important;
                content: " ";
                background: @fa-uid no-repeat;  
                background-size: contain;  
                background-position: center
            }
            &:after {
                content:  "";
                margin-left: -29px;
            }
        }
    }
}

Спасибо, помогло)