body {
    background: url(img/background-image-landing-page.png);
    background-repeat: no-repeat;
    background-size: cover;
    background-position: center;
    height: 100vh;
    margin: 0;
}

footer {
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    color: white;
    text-align: center;
    width: 100%;
}

@media screen and (max-width: 600px) {

    .background-landing-page {
        opacity: 0;
    }
    
    body {
        background: url(img/background-image-landing-page-mobile.png);    
        background-repeat: no-repeat;
        background-size: cover;
        background-position: center;
        height: 100vh;
        margin: 0;    
    }
}