.cis-slider {
    position: relative;
    max-width: 100%;
    overflow: hidden;
}
.cis-slides {
    display: flex;
}

.cis-slide {
    min-width: 100%;
    display: none;
}

.cis-slide img {
    width: 100%;
    height: auto;
    display: block;
}

.cis-prev, .cis-next {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    background: rgba(0,0,0,0.5);
    color: white;
    border: none;
    padding: 10px;
    cursor: pointer;
    z-index: 10;
}

.cis-prev { left: 10px; }
.cis-next { right: 10px; }

@media (max-width: 600px) {
    .cis-prev, .cis-next {
        padding: 5px;
    }
}