:root {
  color-scheme: dark;
  font-family: Inter, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background: #050711;
  color: #eaf6ff;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  min-height: 100%;
  overflow: hidden;
  background:
    radial-gradient(circle at 50% 50%, rgba(50, 92, 132, 0.16), transparent 48%),
    linear-gradient(180deg, #070916 0%, #02030a 100%);
}

body {
  display: grid;
  place-items: center;
  min-height: 100vh;
}

.shell {
  display: grid;
  place-items: center;
  width: min(100vw, 1200px);
  height: min(100vh, 900px);
  padding: 16px;
}

canvas {
  width: min(100%, calc(100vh * 1.333333));
  max-width: 960px;
  aspect-ratio: 4 / 3;
  height: auto;
  border: 1px solid rgba(133, 224, 255, 0.28);
  border-radius: 18px;
  background: #03050d;
  box-shadow:
    0 0 0 1px rgba(255,255,255,0.04) inset,
    0 28px 90px rgba(0, 0, 0, 0.55),
    0 0 42px rgba(48, 174, 221, 0.12);
}