body {
  font-family: Arial, sans-serif;
  margin: 0;
  padding: 0;
}

header {
  background-color: #333;
  color: #fff;
  padding: 20px;
  text-align: center;
}

.main-content {
  padding: 20px;
}

article {
  background-color: #f4f4f4;
  border-radius: 5px;
  padding: 20px;
  margin-bottom: 20px;
}

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