:root {
  color-scheme: dark;
  --bg: #050810;
  --bg-soft: #09111e;
  --ink: #f4f8ff;
  --muted: #8c99aa;
  --line: rgba(173, 193, 219, 0.18);
  --mint: #73f8d2;
  --mint-soft: rgba(115, 248, 210, 0.24);
  --violet: #8e8cff;
  --violet-soft: rgba(142, 140, 255, 0.2);
  --page-pad: clamp(1.35rem, 4vw, 4rem);
}

* {
  box-sizing: border-box;
}

html {
  min-width: 20rem;
  background: var(--bg);
}

body {
  min-height: 100svh;
  margin: 0;
  overflow-x: hidden;
  background:
    radial-gradient(circle at 52% 42%, rgba(27, 42, 64, 0.42), transparent 38rem),
    linear-gradient(145deg, #04070d 0%, var(--bg) 44%, #07101c 100%);
  color: var(--ink);
  font-family: Inter, ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  -webkit-font-smoothing: antialiased;
}

a {
  color: inherit;
}

.page::before {
  position: fixed;
  inset: var(--page-pad);
  z-index: 3;
  border: 1px solid rgba(255, 255, 255, 0.055);
  border-radius: 1.4rem;
  content: "";
  pointer-events: none;
}

.ambient,
.ambient__glow,
.ambient__grain {
  position: fixed;
  inset: 0;
  pointer-events: none;
}

.ambient {
  overflow: hidden;
}

.ambient__glow {
  width: 34rem;
  height: 34rem;
  border-radius: 50%;
  filter: blur(2px);
  opacity: 0.46;
}

.ambient__glow--left {
  inset: auto auto 7% -16rem;
  background: radial-gradient(circle, var(--mint-soft), transparent 68%);
}

.ambient__glow--right {
  inset: -15rem -12rem auto auto;
  background: radial-gradient(circle, var(--violet-soft), transparent 68%);
}

.ambient__grain {
  opacity: 0.22;
  background-image: repeating-linear-gradient(
    120deg,
    rgba(255, 255, 255, 0.018) 0,
    rgba(255, 255, 255, 0.018) 1px,
    transparent 1px,
    transparent 5px
  );
  mask-image: linear-gradient(to bottom, black, transparent 78%);
}

.shell {
  position: relative;
  z-index: 1;
  display: grid;
  min-height: 100svh;
  grid-template-rows: auto 1fr auto;
  padding: calc(var(--page-pad) + clamp(1.25rem, 2.5vw, 2.4rem));
}

.brand,
.footer {
  display: flex;
  align-items: center;
  letter-spacing: 0.11em;
  text-transform: uppercase;
}

.brand {
  gap: 0.72rem;
  color: #dce6f2;
  font-size: 0.68rem;
  font-weight: 640;
}

.brand__mark {
  width: 0.52rem;
  height: 0.52rem;
  border: 1px solid var(--mint);
  border-radius: 50%;
  box-shadow: 0 0 1.1rem var(--mint-soft);
}

.hero {
  position: relative;
  align-self: center;
  width: min(100%, 71rem);
  margin: clamp(3rem, 8vh, 7rem) auto;
}

.signal {
  position: relative;
  width: min(100%, 43rem);
  height: 1.1rem;
  margin-bottom: clamp(2.4rem, 6vh, 4.5rem);
}

.signal__track {
  position: absolute;
  top: 50%;
  right: 0.4rem;
  left: 0.4rem;
  height: 1px;
  overflow: hidden;
  background: linear-gradient(90deg, var(--mint), var(--line) 40%, var(--line) 60%, var(--violet));
}

.signal__track::after {
  position: absolute;
  inset: 0;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.68), transparent);
  content: "";
  transform: translateX(-100%);
  animation: scan 4.8s ease-in-out infinite;
}

.signal__node,
.signal__halo,
.signal__pulse,
.signal__gap {
  position: absolute;
  top: 50%;
  border-radius: 50%;
  transform: translate(-50%, -50%);
}

.signal__node {
  z-index: 2;
  width: 0.66rem;
  height: 0.66rem;
  background: var(--mint);
  box-shadow: 0 0 1.35rem rgba(115, 248, 210, 0.75);
}

.signal__node--origin,
.signal__halo--origin {
  left: 0;
}

.signal__node--destination,
.signal__halo--destination {
  left: 100%;
}

.signal__node--destination {
  background: var(--violet);
  box-shadow: 0 0 1.35rem rgba(142, 140, 255, 0.75);
}

.signal__halo {
  z-index: 1;
  width: 1.8rem;
  height: 1.8rem;
  border: 1px solid rgba(115, 248, 210, 0.28);
  animation: breathe 3.2s ease-in-out infinite;
}

.signal__halo--destination {
  border-color: rgba(142, 140, 255, 0.3);
  animation-delay: -1.6s;
}

.signal__pulse {
  z-index: 3;
  left: 0;
  width: 0.27rem;
  height: 0.27rem;
  background: #eafff9;
  box-shadow: 0 0 0.8rem var(--mint);
  animation: transit 5.2s linear infinite;
}

.signal__pulse--two {
  animation-delay: -1.75s;
}

.signal__pulse--three {
  animation-delay: -3.5s;
}

.eyebrow {
  margin: 0 0 1.15rem;
  color: var(--mint);
  font-size: clamp(0.66rem, 0.9vw, 0.76rem);
  font-weight: 620;
  letter-spacing: 0.18em;
  text-transform: uppercase;
}

h1 {
  max-width: 10ch;
  margin: 0;
  font-size: clamp(4rem, 11vw, 9.5rem);
  font-weight: 520;
  letter-spacing: -0.068em;
  line-height: 0.82;
  text-wrap: balance;
}

.accent {
  color: var(--violet);
}

.lede {
  max-width: 33rem;
  margin: clamp(2rem, 4vw, 3.1rem) 0 0;
  color: #d8e2ee;
  font-size: clamp(1.15rem, 2.1vw, 1.65rem);
  font-weight: 390;
  letter-spacing: -0.025em;
  line-height: 1.42;
}

.note {
  max-width: 32rem;
  margin: 1.1rem 0 0;
  color: var(--muted);
  font-size: clamp(0.86rem, 1.2vw, 0.98rem);
  line-height: 1.7;
}

.footer {
  justify-content: space-between;
  gap: 1.2rem;
  color: #647287;
  font-size: 0.59rem;
  font-weight: 580;
}

.footer__status {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
}

.footer__status i {
  width: 0.34rem;
  height: 0.34rem;
  border-radius: 50%;
  background: var(--mint);
  box-shadow: 0 0 0.8rem var(--mint);
  animation: status 2.2s ease-in-out infinite;
}

.error-code {
  position: absolute;
  top: -0.55em;
  right: 0;
  z-index: -1;
  color: rgba(162, 175, 198, 0.035);
  font-size: clamp(10rem, 32vw, 30rem);
  font-weight: 700;
  letter-spacing: -0.09em;
  line-height: 0.8;
  user-select: none;
}

.signal--broken .signal__track {
  background: linear-gradient(90deg, var(--mint), var(--line) 44%, transparent 44%, transparent 56%, var(--line) 56%, var(--violet));
}

.signal--broken .signal__track::after {
  display: none;
}

.signal__gap {
  left: 50%;
  width: 1.05rem;
  height: 1.05rem;
  border: 1px solid rgba(255, 255, 255, 0.16);
  background: var(--bg);
}

.signal--broken .signal__pulse {
  animation-name: lost;
  animation-duration: 3.4s;
}

.page--not-found .eyebrow {
  color: #aeadff;
}

.return-link {
  display: inline-flex;
  align-items: center;
  gap: 1.3rem;
  margin-top: clamp(1.8rem, 4vw, 2.8rem);
  padding: 0.82rem 0;
  border-bottom: 1px solid rgba(115, 248, 210, 0.5);
  color: #e4fff7;
  font-size: 0.78rem;
  font-weight: 620;
  letter-spacing: 0.09em;
  text-decoration: none;
  text-transform: uppercase;
  transition: gap 180ms ease, border-color 180ms ease, color 180ms ease;
}

.return-link:hover,
.return-link:focus-visible {
  gap: 1.7rem;
  border-color: var(--mint);
  color: white;
}

.return-link:focus-visible {
  border-radius: 0.2rem;
  outline: 2px solid var(--violet);
  outline-offset: 0.45rem;
}

.footer__status--muted i {
  background: var(--violet);
  box-shadow: 0 0 0.8rem var(--violet-soft);
}

@keyframes transit {
  0% {
    left: 0;
    opacity: 0;
  }
  8%, 88% {
    opacity: 1;
  }
  100% {
    left: 100%;
    opacity: 0;
  }
}

@keyframes lost {
  0% {
    left: 0;
    opacity: 0;
  }
  12%, 75% {
    opacity: 1;
  }
  83% {
    left: 47%;
    opacity: 0;
  }
  100% {
    left: 47%;
    opacity: 0;
  }
}

@keyframes scan {
  0%, 20% {
    transform: translateX(-100%);
  }
  76%, 100% {
    transform: translateX(100%);
  }
}

@keyframes breathe {
  0%, 100% {
    opacity: 0.5;
    transform: translate(-50%, -50%) scale(0.82);
  }
  50% {
    opacity: 1;
    transform: translate(-50%, -50%) scale(1.12);
  }
}

@keyframes status {
  0%, 100% {
    opacity: 0.55;
  }
  50% {
    opacity: 1;
  }
}

@media (max-width: 42rem) {
  .page::before {
    border-radius: 1rem;
  }

  .shell {
    padding: calc(var(--page-pad) + 1.15rem);
  }

  .hero {
    margin-block: 3.5rem;
  }

  .signal {
    width: 87%;
  }

  h1 {
    font-size: clamp(3.65rem, 20vw, 6.6rem);
  }

  .footer {
    align-items: flex-end;
  }

  .footer__status {
    max-width: 11rem;
    justify-content: flex-end;
    text-align: right;
  }
}

@media (max-height: 44rem) and (min-width: 43rem) {
  .shell {
    padding-block: calc(var(--page-pad) + 1rem);
  }

  .hero {
    margin-block: 2.6rem;
  }

  .signal {
    margin-bottom: 2rem;
  }

  h1 {
    font-size: clamp(4rem, 14vh, 6.5rem);
  }

  .lede {
    margin-top: 1.5rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
  }

  .signal__pulse--one {
    left: 34%;
    opacity: 1;
  }

  .signal__pulse--two {
    left: 63%;
    opacity: 1;
  }

  .signal__pulse--three {
    left: 82%;
    opacity: 1;
  }

  .signal--broken .signal__pulse {
    left: 34%;
  }
}