span.on_sale {
    left: auto !important;
    right: 10px;
    top: 10px;
    color: #FFFFFF;
}


#product #productsattr_grid span.on_sale {
    display:none;
}

@media (max-width: 767px){
    a span.on_sale {
        font-size: 10px;
        height: 30px;
        line-height: 26px;
        min-width: 30px;
        width: 30px;
    }
}