body {
  font-family: system-ui, Arial, sans-serif;
  margin: 0;
  background: #f4f4f4;
  color: #111;
}

main {
  max-width: 800px;
  margin: 60px auto;
  padding: 24px;
  background: white;
  border-radius: 16px;
}

h1 {
  margin-top: 0;
}