.dwstroy_tinkoff {
    background-image: url("/bitrix/images/tinkoff.id/tinkoff.png") !important;
    background-size: 16px 16px;
    width:16px;
    height:16px;
    background-repeat:no-repeat;
}
.bx-authform-social ul li .bx-authform-social-icon.dwstroy_tinkoff {
    background-image: url("/bitrix/images/tinkoff.id/tinkoff.png") !important;
    width: 35px;
    height: 35px;
    background-size: 35px 35px;
}