a.single_sign_on{
    display:block;
    margin: 0 auto;
    padding: 0 auto;
    width:225px;
    height:50px;
    background-repeat: no-repeat;
    background-image: url(../img/microsoft_signin_white.png);
    /* font:Segoe UI Regular;
    font-size:  15px;
    font-weight: 600;
    color: black;
    border: solid 1px; */

}