html,
body {
    height: 100%;
}
html {
    display: table;
    margin: auto;
}
body {
    display: table-cell;
    vertical-align: middle;
    
}

#login-page {
   width: 500px;
}

.card {
     position: absolute;
     left: 50%;
     top: 50%;
     -moz-transform: translate(-50%, -50%);
     -webkit-transform: translate(-50%, -50%);
     -ms-transform: translate(-50%, -50%);
     -o-transform: translate(-50%, -50%);
     transform: translate(-50%, -50%);
}