* {box-sizing: border-box;}
.img-comp-container {
    position: relative;
    width:100%;
    height: 500px; /*should be the same height as the images*/
}
.img-comp-img {
    position: absolute;
    width: auto;
    height: auto;
    overflow:hidden;
}
.img-comp-img img {
    display:block;
    vertical-align:middle;
}
.img-comp-slider {
    position: absolute;
    z-index:9;
    cursor: ew-resize;
    /*set the appearance of the slider:*/
    width: 40px;
    height: 40px;
    background-color: #13f300;
    opacity: 0.95;
    border-radius: 50%;
}

/* On smaller screens, decrease text size */
@media only screen and (max-width: 1600px) {
    .img-comp-img, img {width: 100%}
}