#block-stuslider {
    position: relative;
    width: 100%;
    height: 280px;
    overflow: hidden;
}

#block-stuslider img {
    transition: opacity 1.5s;
    position: absolute;
    top: 0;
    width: 100%;
    height: auto;
    left: 50%;
    transform: translateX(-50%);
    opacity:0;
}

@media screen and (max-width: 992px) {
    #block-stuslider img {
        width: auto;
        height: 100%;
    }
}

#block-stuslider img.fadeIn {
    opacity:1;
}