body {
    background: url(../images/desktop-coming-soon.png) no-repeat center center #3a0094;
    display: flex; 
    flex-direction: row; 
    align-items: center; 
    justify-content: center;
    margin: 0;
    padding: 0;
    min-height: 100vh;
}

@media (min-width: 767.98px) and (max-width: 991.98px) {
    body {
        background: url(../images/mobile-coming-soon.png) no-repeat center center #3a0094;
        background-size: contain;
    }
}

@media (min-width: 575.98px) and (max-width: 767.98px) {
    body {
        background: url(../images/mobile-coming-soon.png) no-repeat center center #3a0094;
        background-size: contain;
    }
}

@media (max-width: 575.98px) {
    body {
        background: url(../images/mobile-coming-soon.png) no-repeat center center #3a0094;
        background-size: contain;
    }
}