.slideshow {
    list-style: none;
    z-index: 1;
}

.slideshow li span {
    -webkit-filter: grayscale(100%);
    /* Safari 6.0 - 9.0 */
    filter: grayscale(100%);
    width: 100%;
    height: 92.2%;
    position: absolute;
    top: 1.5cm;
    left: 0px;
    color: transparent;
    background-size: cover;
    background-position: 50% 50%;
    background-repeat: none;
    opacity: 0;
    z-index: 0;
    -webkit-backface-visibility: hidden;
    backface-visibility: hidden;
    -webkit-animation: imageAnimation 18s linear infinite 0s;
    -moz-animation: imageAnimation 18s linear infinite 0s;
    animation: imageAnimation 18s linear infinite 0s;
}


.slideshow li:nth-child(1) span {
    background-image: url(pictures/schueco/schueco1.jpg);
    -webkit-animation-delay: 0s;
    -moz-animation-delay: 0s;
    animation-delay: 0s;
}

.slideshow li:nth-child(2) span {
    background-image: url(pictures/schueco/schueco2.jpg);
    -webkit-animation-delay: 6s;
    -moz-animation-delay: 6s;
    animation-delay: 6s;
}

.slideshow li:nth-child(3) span {
    background-image: url(pictures/schueco/schueco3.jpg);
    -webkit-animation-delay: 12s;
    -moz-animation-delay: 12s;
    animation-delay: 12s;
}


@-webkit-keyframes imageAnimation {
    0% {
        opacity: 0;
        -webkit-animation-timing-function: ease-in;
    }

    33.33% {
        opacity: 1;
        -webkit-animation-timing-function: ease-in;
    }

    66.66% {
        opacity: 0;
        -webkit-animation-timing-function: ease-in;
    }

    100% {
        opacity: 0;
    }
}