.background {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: url('../images/fabrica.jpg');
    background-size: cover;
    background-position: center;
    background-attachment: fixed;
    z-index: -1;
}

.background::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.8);
    z-index: -1;
}