body {
  font-family: system-ui, Arial, sans-serif;
  margin: 20px;
  background: #f5f6fa;
  color: #222;
}

header {
  margin-bottom: 30px;
}

header h1 {
  margin-bottom: 5px;
}

h2 {
  margin-top: 20px;
  color: #333;
}