:root { color-scheme: dark; }
html, body { height: 100%; }
body {
  background: radial-gradient(1200px 600px at 50% 0%,
              rgba(255,255,255,0.08),
              rgba(255,255,255,0.02) 30%,
              rgba(0,0,0,0) 60%),
              #0b0b0b;
  background-attachment: fixed;
}