html,
body {
    height: 100%;
}

#page-container {
    height: 100%;
}

#content {
    height:100%;
}

.bg {
    /* The image used */
    background-image: url("/gfx/background.jpg");

    /* Full height */
    height: 100%; 

    /* Center and scale the image nicely */
    background-position: top;
    background-repeat: no-repeat;
    background-size: cover;

    margin-bottom: -30px;
    margin-left: -30px;
    margin-right: -30px;
    margin-top: -40px;
}

.btn-100 {
    width: 100%;
}