#stage > canvas:not(.tectonic-letterbox-ambient) {
  position: relative;
  z-index: 1;
}

body.is-ready:not(.is-letterbox-ready) #stage > canvas:not(.tectonic-letterbox-ambient) {
  visibility: hidden;
}

#stage .tectonic-letterbox-ambient {
  position: absolute;
  inset: 0;
  z-index: 0;
  width: 100%;
  height: 100%;
  background: #000;
  outline: 0;
  opacity: 0;
  pointer-events: none;
  filter: blur(26px) brightness(0.42) saturate(0.64);
}

#stage.has-active-letterbox-atmosphere .tectonic-letterbox-ambient {
  opacity: 0.88;
}

#stage.has-active-letterbox-atmosphere > canvas:not(.tectonic-letterbox-ambient) {
  outline: 0;
  -webkit-mask-image: linear-gradient(
    to bottom,
    transparent 0,
    rgba(0, 0, 0, 0.18) var(--tectonic-letterbox-feather-soft),
    rgba(0, 0, 0, 0.72) var(--tectonic-letterbox-feather-dense),
    #000 var(--tectonic-letterbox-feather),
    #000 calc(100% - var(--tectonic-letterbox-feather)),
    rgba(0, 0, 0, 0.72) calc(100% - var(--tectonic-letterbox-feather-dense)),
    rgba(0, 0, 0, 0.18) calc(100% - var(--tectonic-letterbox-feather-soft)),
    transparent 100%
  );
  mask-image: linear-gradient(
    to bottom,
    transparent 0,
    rgba(0, 0, 0, 0.18) var(--tectonic-letterbox-feather-soft),
    rgba(0, 0, 0, 0.72) var(--tectonic-letterbox-feather-dense),
    #000 var(--tectonic-letterbox-feather),
    #000 calc(100% - var(--tectonic-letterbox-feather)),
    rgba(0, 0, 0, 0.72) calc(100% - var(--tectonic-letterbox-feather-dense)),
    rgba(0, 0, 0, 0.18) calc(100% - var(--tectonic-letterbox-feather-soft)),
    transparent 100%
  );
}

.tectonic-letterbox-band {
  position: absolute;
  left: 0;
  z-index: 2;
  display: none;
  width: 100%;
  height: calc(var(--tectonic-letterbox-bar) + var(--tectonic-letterbox-feather));
  pointer-events: none;
}

#stage.has-active-letterbox-atmosphere .tectonic-letterbox-band {
  display: block;
}

.tectonic-letterbox-band--top {
  top: 0;
  background: linear-gradient(
    to bottom,
    rgba(0, 0, 0, 0.99) 0,
    rgba(0, 0, 0, 0.88) var(--tectonic-letterbox-bar-mid),
    rgba(0, 0, 0, 0.46) var(--tectonic-letterbox-bar),
    rgba(0, 0, 0, 0.15) var(--tectonic-letterbox-feather-mid),
    rgba(0, 0, 0, 0) 100%
  );
}

.tectonic-letterbox-band--bottom {
  bottom: 0;
  background: linear-gradient(
    to top,
    rgba(0, 0, 0, 0.99) 0,
    rgba(0, 0, 0, 0.88) var(--tectonic-letterbox-bar-mid),
    rgba(0, 0, 0, 0.46) var(--tectonic-letterbox-bar),
    rgba(0, 0, 0, 0.15) var(--tectonic-letterbox-feather-mid),
    rgba(0, 0, 0, 0) 100%
  );
}