body {
    margin: 0;
    padding: 0;
}
#auth_form {
    width: 100%;
    text-align: center;
}
#auth_form .logo {
    width: 100%;
    height: 20vh;
    margin: 2em 0 2em 0;
    background: url('img/logo.jpg') top center no-repeat;
    background-size: contain;    
}
#auth_form input {
    display: block;
    margin: 0 auto 1em auto;
}