#gallery_side__photo-1, .portfolio_section-slider__img-1 {
    background-image: url(../img/img-case-1.jpg);
}

#gallery_side__photo-2 {
    background-image: url(../img/img-case-2.jpg)
}

#gallery_side__photo-3 {
    background-image: url(../img/img-case-3.jpg)
}

#gallery_side__photo-4 {
    background-image: url(../img/img-case-4.jpg)
}

#gallery_side__photo-5 {
    background-image: url(../img/img-case-5.jpg)
}

#gallery_side__photo-6 {
    background-image: url(../img/img-case-6.jpg)
}