.background {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  pointer-events: none;
  z-index: var(--z-index-background);
  animation: appear var(--layout-transition-speed-slow) 1;
  display: none;
}

.is-background-image-show .background {
  display: block;
}

.background-image {
  background-image: var(--background-image);
  /* background-image: url(https://source.unsplash.com/random/1920x1080/?night); */
  background-attachment: fixed;
  background-size: cover;
  background-position: center;
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  display: block;
  opacity: var(--background-opacity);
  transform: scale(var(--background-scale));
  filter: blur(var(--background-blur)) grayscale(var(--background-grayscale));
}

.background-accent {
  background-color: rgba(var(--theme-accent), var(--background-accent-opacity));
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  display: block;
}