body {
  margin: 0;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: system-ui, sans-serif;
  background: #0f172a;
  color: #f8fafc;
}
main {
  text-align: center;
  padding: 2rem;
}
h1 {
  font-size: 2.5rem;
  margin-bottom: 0.5rem;
}