lightbox.css

.lightbox {
  position: fixed;
  top: 0; left: 0; right: 0; bottom: 0;
  z-index: 999;
  background: rgba(0, 0, 0, 0.85);
  opacity: 0;
}
.lightbox::before {
  position: absolute;
  top: 50%;
  left: 50%;
  z-index: 0;
  padding: .5em 1em;
  opacity: 0;
  transform: translate(-50%, -50%);
  background: black;
  color: white;
  content: "LOADING…";
}
.lightbox .lightbox-close a, .lightbox .lightbox-prev a, .lightbox .lightbox-next a {
  position: absolute;
  top: 0; left: 0; right: 0; bottom: 0;
  text-decoration: none;
  font-size: 4em;
}
.lightbox .lightbox-prev a {
  right: 80%;
}
.lightbox .lightbox-next a {
  left: 80%;
}
.lightbox .lightbox-prev a div, .lightbox .lightbox-next a div {
  position: relative;
  top: 50%;
  height: 15vh;
  line-height: 15vh;
  margin: 0 0.25em;
  transform: translateY(-50%);
  text-align: center;
  color: white;
  border: 0.0625em solid white;
  opacity: 0.5;
}
.lightbox .lightbox-wrapper {
  position: absolute;
  top: 3%;
  left: 20%;
  right: 20%;
  bottom: 9%;
  z-index: 1;
  opacity: 1.0;
  transform: scale(0.8);
  pointer-events: none;
}
.lightbox .lightbox-image {
  position: absolute;
  top: 0; left: 0; right: 0; bottom: 0;
  background: center / contain no-repeat;
}
.lightbox .lightbox-progress {
  text-align: center;
  opacity: 0.5;
  position: relative;
  top: 94%;
  height: 0;
}
.lightbox .lightbox-progress a {
  border: 0.0625em solid white;
  margin: 0 -0.03125em;
}
.lightbox .lightbox-progress a.current {
  background-color: white;
}

.lightbox:target {
  opacity: 1;
  visibility: visible;
}
.lightbox:target::before {
  opacity: 1;
  transition: opacity 0.75s cubic-bezier(0.05, 0.85, 0.15, 1.0) 0.25s;
}
.lightbox:target .lightbox-wrapper {
  opacity: 1;
  transform: scale(1);
  transition: 0.75s cubic-bezier(0.05, 0.85, 0.15, 1.0);
}
.lightbox:target .lightbox-image-container {
  display: block;
}