:root {
  color-scheme: dark;
  --ink: #effff7;
  --hot: #51ff99;
  --cold: #ff2ecb;
  --bg: #050507;
}

* { box-sizing: border-box; }

html,
body {
  width: 100%;
  min-height: 100%;
  margin: 0;
  overflow: hidden;
  background: var(--bg);
}

body {
  min-height: 100svh;
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", monospace;
}

body::before,
body::after {
  position: fixed;
  inset: 0;
  pointer-events: none;
  content: "";
}

body::before {
  z-index: 3;
  background:
    repeating-linear-gradient(0deg, rgb(0 0 0 / 0) 0 2px, rgb(0 0 0 / .22) 3px),
    radial-gradient(circle at 50% 47%, transparent 28%, rgb(0 0 0 / .72) 100%);
  mix-blend-mode: multiply;
}

body::after {
  z-index: 4;
  opacity: .2;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 180 180' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)' opacity='.35'/%3E%3C/svg%3E");
  animation: grain .18s steps(2) infinite;
}

canvas {
  position: fixed;
  inset: 0;
  width: 100%;
  height: 100%;
}

main {
  position: relative;
  z-index: 2;
  display: grid;
  min-height: 100svh;
  place-items: center;
  perspective: 900px;
}

.signal {
  position: relative;
  width: max-content;
  max-width: 94vw;
  margin: 0;
  filter: drop-shadow(0 0 1.8rem rgb(81 255 153 / .18));
  transform: rotateX(var(--rx, 0deg)) rotateY(var(--ry, 0deg));
  transition: transform 180ms ease-out;
}

.banner {
  margin: 0;
  color: var(--ink);
  font: 800 clamp(.72rem, min(6.3vw, 10.2vh), 8rem)/.86 ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", monospace;
  letter-spacing: -.08em;
  white-space: pre;
  text-shadow:
    0 0 .08em var(--ink),
    0 0 .28em rgb(81 255 153 / .58),
    0 0 .9em rgb(81 255 153 / .22);
  user-select: none;
}

.ghost {
  position: absolute;
  inset: 0;
  opacity: .48;
  mix-blend-mode: screen;
}

.ghost-a {
  color: var(--hot);
  clip-path: polygon(0 8%, 100% 8%, 100% 33%, 0 33%, 0 68%, 100% 68%, 100% 78%, 0 78%);
  transform: translate(-.035em, 0);
  animation: split-a 3.8s steps(1) infinite;
}

.ghost-b {
  color: var(--cold);
  clip-path: polygon(0 35%, 100% 35%, 100% 64%, 0 64%, 0 82%, 100% 82%, 100% 94%, 0 94%);
  transform: translate(.035em, 0);
  animation: split-b 3.8s steps(1) infinite;
}

.signal.burst .ghost-a { animation: burst-a 180ms steps(2) 2; }
.signal.burst .ghost-b { animation: burst-b 180ms steps(2) 2; }

@keyframes split-a {
  0%, 90%, 100% { transform: translate(-.035em, 0); }
  91% { transform: translate(-.13em, .025em); }
  93% { transform: translate(.06em, -.02em); }
}

@keyframes split-b {
  0%, 88%, 100% { transform: translate(.035em, 0); }
  89% { transform: translate(.14em, -.02em); }
  92% { transform: translate(-.07em, .025em); }
}

@keyframes burst-a {
  0% { transform: translate(-.25em, .04em); }
  100% { transform: translate(.08em, -.03em); }
}

@keyframes burst-b {
  0% { transform: translate(.22em, -.04em); }
  100% { transform: translate(-.06em, .03em); }
}

@keyframes grain {
  0% { transform: translate(0); }
  25% { transform: translate(-1%, 1%); }
  50% { transform: translate(1%, -1%); }
  75% { transform: translate(.5%, 1%); }
}

@media (prefers-reduced-motion: reduce) {
  body::after,
  .ghost { animation: none; }
  .signal { transition: none; }
}