.client-list-slider {
    margin: 30px 0;
}
.client-list-slider-item {
    border: 1px solid #cbcbcb;
    height: 0;
    padding-top: 100%;
    background-size: contain;
    background-repeat: no-repeat;
    background-position: center;
}
.client-list-slider .slick-slider {
    margin: 0 1px;
}