janus/styles/main.css

/* Basics */

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

* + * {
  margin-top: 1em;
}

:root {
  box-sizing: border-box;
  line-height: 1.5;
  font-family: sans-serif;
  font-size: calc(2vw + 2em);
}

/* Layout */
body {
  display: flex;
  flex-direction: column;
  padding: 0;
  margin: 0;
  background-color: black;
  color: white;
  /*background-image: url('30000-light-stripes.gif');
  background-size: cover;
  box-shadow: 0 0 10vmin black inset, 0 0 10vmin black inset;*/
}

main {
  margin-top: 0;
  perspective: 100vmin;
  transform-style: preserve-3d;
  overflow: hidden;
  height: 100vh;
}

/* Components */
section {
  position: absolute;
  display: flex;
  flex-direction: column;
  width: 100%;
  height: 100%;
  margin: 0;
  padding: 1em;
  overflow: hidden;
  transition: transform ease 1s, opacity ease 1s, visibility step-end 1s;
  transform-origin: 50% 50%;
  text-align: center;
}

[janus-timeline='past'] {
}

[janus-timeline='present'] {
  transition: transform ease 1s, opacity ease 1s, visibility step-start 1s;
}

[janus-timeline='future'] {
  visibility: hidden;
}

section[janus-timeline='past'] {
  transform: translate3d(0, 0, 100vmin);
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
}

section[janus-timeline='present'] {
  transform: none;
  opacity: 1;
}

section[janus-timeline='future'] {
  transform: translate3d(0, 0, -25vmin);
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
}

section.image > img {
  position: absolute;
  margin: 0;
  top: 0;
  left: 0;
  height: 100%;
  width: 100%;
  object-fit: cover;
  z-index: -1;
}