:root {
  color-scheme: dark;
  --bg: #07111f;
  --panel: rgba(12, 27, 48, .76);
  --line: rgba(148, 191, 255, .16);
  --text: #f5f8ff;
  --muted: #a8bad2;
  --cyan: #31d6df;
  --blue: #5d7cff;
}

* { box-sizing: border-box; }

html, body { min-height: 100%; }

body {
  margin: 0;
  display: grid;
  place-items: center;
  padding: 28px;
  overflow-x: hidden;
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  color: var(--text);
  background:
    radial-gradient(circle at 18% 20%, rgba(49, 214, 223, .16), transparent 32rem),
    radial-gradient(circle at 84% 75%, rgba(93, 124, 255, .18), transparent 34rem),
    var(--bg);
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  opacity: .32;
  background-image:
    linear-gradient(rgba(255,255,255,.035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,.035) 1px, transparent 1px);
  background-size: 42px 42px;
  mask-image: linear-gradient(to bottom, #000, transparent 88%);
}

.card {
  position: relative;
  width: min(760px, 100%);
  padding: clamp(30px, 6vw, 64px);
  border: 1px solid var(--line);
  border-radius: 28px;
  background: var(--panel);
  box-shadow: 0 32px 100px rgba(0,0,0,.42);
  backdrop-filter: blur(18px);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 54px;
  color: var(--text);
  font-size: 20px;
  font-weight: 750;
  letter-spacing: -.02em;
}

.brand-logo {
  width: 54px;
  height: 54px;
  display: block;
  object-fit: contain;
  filter: drop-shadow(0 10px 22px rgba(49,214,223,.2));
}

.eyebrow {
  margin: 0 0 14px;
  color: var(--cyan);
  font-size: 13px;
  font-weight: 800;
  letter-spacing: .16em;
  text-transform: uppercase;
}

h1 {
  max-width: 650px;
  margin: 0;
  font-size: clamp(38px, 7vw, 68px);
  line-height: 1.02;
  letter-spacing: -.055em;
}

p {
  max-width: 590px;
  margin: 24px 0 0;
  color: var(--muted);
  font-size: clamp(17px, 2.2vw, 20px);
  line-height: 1.65;
}

.status {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-top: 38px;
  color: #c9d7e8;
  font-size: 14px;
}

.dot {
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: #47e6a4;
  box-shadow: 0 0 0 7px rgba(71,230,164,.1), 0 0 22px rgba(71,230,164,.7);
}

.error-code {
  position: absolute;
  top: 24px;
  right: 34px;
  color: rgba(255,255,255,.06);
  font-size: clamp(72px, 18vw, 154px);
  font-weight: 900;
  letter-spacing: -.08em;
  line-height: 1;
  user-select: none;
}

.button {
  display: inline-flex;
  margin-top: 34px;
  padding: 13px 18px;
  border: 1px solid var(--line);
  border-radius: 12px;
  color: var(--text);
  background: rgba(255,255,255,.045);
  text-decoration: none;
  font-weight: 700;
}

.button:hover { background: rgba(255,255,255,.09); }

@media (max-width: 520px) {
  body { padding: 16px; }
  .card { border-radius: 22px; }
  .brand { margin-bottom: 42px; }
  .error-code { top: 18px; right: 24px; }
}