:root { color-scheme: dark; }
* { box-sizing: border-box; }
html, body {
  margin: 0;
  padding: 0;
  width: 100%;
  height: 100%;
  overflow: hidden;
  background: #0f172a;
  color: #e2e8f0;
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}