gistfile1.txt

<style>
/*
  Lightbox credit: Alex Rosenkranz
  https://gist.github.com/arosenkranz/3359c65fbfda36f17f622ff624b74aea
*/

.lightbox {
  display: none;
  position: fixed;
  justify-content: center;
  align-items: center;
  z-index: 999;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  padding: 1rem;
  background: rgba(0, 0, 0, 0.8);
}

.lightbox:target {
  display: flex;
}

.lightbox img {
  max-height: 100%
}

</style>