body {
  font-family: Arial, sans-serif;
  margin: 0;
  padding: 0;
  line-height: 1.6;
  background: #f4f4f4;
  color: #333;
}
header, footer {
  background: #007BFF;
  color: white;
  text-align: center;
  padding: 1em 0;
}
section {
  padding: 20px;
  background: white;
  margin: 20px;
  border-radius: 8px;
}
ul {
  padding-left: 20px;
}
.btn {
  display: inline-block;
  margin-top: 10px;
  padding: 10px 20px;
  background: #28a745;
  color: white;
  text-decoration: none;
  border-radius: 5px;
}