body{
    background-color:white;
}

header{
    position: absolute;
    width: 100%;
    top: 0;
    left: 0;
}

.login-form-center {
    display: table;
    height: 100%
}

.login-form-center > div {
    display: table-cell;
    vertical-align: middle;
}

.login-form-center .panel {
    margin-bottom: 0;
}