body {
  font-family: Arial, sans-serif;
  margin: 0;
  background: #f9f9f9;
  color: #333;
}

header {
  background: #4CAF50;
  color: white;
  padding: 20px;
  text-align: center;
}

main {
  padding: 20px;
}

article {
  background: white;
  margin-bottom: 20px;
  padding: 15px;
  border-radius: 5px;
  box-shadow: 0 2px 5px rgba(0,0,0,0.1);
}

footer {
  background: #333;
  color: white;
  text-align: center;
  padding: 10px;
}