body {
  font-family: Arial, Helvetica, sans-serif;
  margin: 0;
  padding: 0;
  color: #222;
  background-color: #f5f5f5;
}

header {
  background: #1f2933;
  color: #fff;
  padding: 30px;
  text-align: center;
}

nav {
  background: #111827;
  padding: 10px;
  text-align: center;
}

nav a {
  color: #fff;
  margin: 0 15px;
  text-decoration: none;
  font-weight: bold;
}

section {
  padding: 40px;
  background: #fff;
  margin: 20px auto;
  max-width: 900px;
}

footer {
  text-align: center;
  padding: 20px;
  font-size: 14px;
  color: #555;
}