#start {
    top: 0;
    left: 0;
    height: 100%;
    background: url(../pictures/background2.jpg);
    background-color: white;
    background-position: center center;
    background-repeat: no-repeat;
    background-size: cover;
    background-attachment: fixed;
    scroll-snap-align: start;
}

#start .container {
    display: flex;
    align-items: center;
    justify-content: center;
    height: 100%;
}

@media screen and (max-width: 900px) {
    #start {
        background-position: bottom;
        background-attachment: local;
    }
}