.not-found-container {
    position: fixed; /* Use absolute if you don't want it to cover the entire viewport */
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: url('/assets/images/enerco/404-enerco.jpg') no-repeat center center;
    background-size: cover;
    display: flex;
    justify-content: center;
    align-items: center;
    text-align: center;
}

@media screen and (max-width: 667px) {
    .not-found-container {
        width: 100%;
        height: 65%;
        margin-top: 20%;
    }
}