.page-background {
    position: relative;
    max-width: 100%;
}

.page-background .background-img {
    position: fixed;
    top: 0;
    left: 0;
    max-width: 100%;
    width: 100%;
    height: 100vh;
    z-index:-1;
    background-repeat: no-repeat;
    background-position: center;
    background-size: cover;
}