html {
  box-sizing: border-box;
  height: 100%;
}

*,
*::before,
*::after {
  box-sizing: inherit;
  margin: 0;
  padding: 0;
}

.container {
  display: -webkit-box;
  display: flex;
  -webkit-box-pack: center;
          justify-content: center;
}

.thumbnails {
  display: -webkit-box;
  display: flex;
  -webkit-box-orient: horizontal;
  -webkit-box-direction: normal;
          flex-direction: row;
  line-height: 0;
}
.thumbnails li {
  -webkit-box-flex: 1;
          flex: auto;
}
.thumbnails a {
  display: block;
}
.thumbnails img {
  width: 20vmin;
  height: 10vmin;
  -o-object-fit: cover;
     object-fit: cover;
  -o-object-position: top;
     object-position: top;
  margin: 2vmin;
  border: 1px solid white;
}

.slides {
  overflow: hidden;
  width: 75vmin;
  height: 100vmin;
}
.slides li {
  width: 75vmin;
  height: 100vmin;
  position: absolute;
  z-index: 1;
}
.slides img {
  height: 100vmin;
  -o-object-fit: cover;
     object-fit: cover;
  -o-object-position: top;
     object-position: top;
}

.slides li:target {
  z-index: 3;
  -webkit-animation: slide 1s 1;
}

.slides li:not(:target) {
  -webkit-animation: hidden 1s 1;
}

@-webkit-keyframes slide {
  0% {
    -webkit-transform: translateY(-100%);
            transform: translateY(-100%);
  }
  100% {
    -webkit-transform: translateY(0%);
            transform: translateY(0%);
  }
}

@keyframes slide {
  0% {
    -webkit-transform: translateY(-100%);
            transform: translateY(-100%);
  }
  100% {
    -webkit-transform: translateY(0%);
            transform: translateY(0%);
  }
}
@-webkit-keyframes hidden {
  0% {
    z-index: 2;
  }
  100% {
    z-index: 2;
  }
}
@keyframes hidden {
  0% {
    z-index: 2;
  }
  100% {
    z-index: 2;
  }
}