body::after {
    content: "";
    background: url("../img/bg_login.jpg");
    background-position: center;
    background-size: 50%;
    background-repeat: no-repeat;
    /*opacity: 0.2;*/
    top: 0;
    left: 0;
    bottom: 0;
    right: 0;
    position: absolute;
    z-index: -1;
}

form.well {
    background-color: rgba(255,255,255,0.1) !important;
}