body {
  min-height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
  background: #f8f8f8;
}

* {
  box-sizing: border-box;
}

.center-marker {
  height: 50px;
  width: 100vw;
  position: absolute;
  top: calc(50% - 360px);
  display: none;
}
.center-marker div {
  height: 30px;
  width: 1px;
  margin: auto;
  background: #8882;
}

.js-slideshow {
  --offset: 1600px;
  --overlap: 2;
  --image-gap: 6;
  --offset-time: 0.48s;
  --thumb-border-radius: 0;
  --thumb-size: 50;
  --thumbs-width: 20000;
  width: calc(100vw - 0px);
  max-width: 880px;
  position: relative;
  -webkit-user-select: none;
     -moz-user-select: none;
      -ms-user-select: none;
          user-select: none;
}
.js-slideshow__slides-wrapper {
  position: relative;
  height: 0;
  width: 100%;
  padding-bottom: 50%;
  overflow: hidden;
}
.js-slideshow__slides {
  position: absolute;
  height: 100%;
  width: 40000px;
  left: 50%;
  transform: translate(calc(var(--offset) * -1), 0);
  display: flex;
  flex-flow: row nowrap;
  justify-content: flex-start;
  transition: transform var(--offset-time) ease;
}
.js-slideshow__slides img {
  height: 100%;
  display: block;
  margin-left: calc(var(--image-gap) * 0.5px);
  margin-right: calc(var(--image-gap) * 0.5px);
}
.js-slideshow__thumbs-wrapper {
  width: 100%;
  height: calc(var(--thumb-size) * 1px + 18px);
  margin-top: calc(var(--image-gap) * 1px);
  position: relative;
  display: block;
  overflow: scroll;
  scroll-behavior: smooth;
}
.js-slideshow__thumbs {
  width: calc(var(--thumbs-width) * 1px);
  display: grid;
  grid-auto-rows: calc(var(--thumb-size) * 1px);
  grid-template-columns: repeat(auto-fit, calc(var(--thumb-size) * 1px));
  grid-gap: calc(var(--image-gap) * 1px);
}
.js-slideshow__thumb-image {
  margin: 0;
  position: relative;
}
.js-slideshow__thumb-image img {
  height: 100%;
  width: 100%;
  display: block;
  border-radius: var(--thumb-border-radius);
  -o-object-fit: cover;
     object-fit: cover;
}
.js-slideshow__thumb-image--selected:after {
  content: "";
  position: absolute;
  top: 0;
  right: 0;
  bottom: 0;
  left: 0;
  border-radius: var(--thumb-border-radius);
  box-shadow: inset 0 0 0 3px rgba(50, 200, 200, 0.8);
}

@media (min-width: 700px) {
  .js-slideshow {
    --thumb-size: 77;
  }
  .js-slideshow__thumbs-wrapper {
    display: block;
  }
}