#adver-location-left, #adver-location-right {
    position: fixed;
    top: calc(100% - 50% - 190px);
    width: 190px;
    height: 320px;
    background: red;
}

#adver-location-left > span, #adver-location-right > span {
    position: absolute;
    display: inline-block;
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background-color: rgba(0, 0, 0, 0.5);
    text-align: center;
    line-height: 17px;
    color: white;
    top: 10px;
}

#adver-location-left  img, #adver-location-right  img{
    width: 100%;
    height: 100%;
}

#adver-location-left {
    left: 0;
}

#adver-location-right {
    right: 0;
}

#adver-location-left > span {
    right: 10px;
}

#adver-location-right > span {
    left: 10px;
}

#adver-location-right > span:hover,#adver-location-left > span:hover {
    cursor: pointer;
}