body {
  font-family: Arial, sans-serif;
  margin: 0;
  padding: 0;
  line-height: 1.6;
  background: #f5f5f5;
}
header {
  background: #2c2c2c;
  color: #fff;
  padding: 20px 0;
  text-align: center;
}
header nav ul {
  list-style: none;
  padding: 0;
}
header nav ul li {
  display: inline;
  margin: 0 10px;
}
header nav ul li a {
  color: #fff;
  text-decoration: none;
}
section {
  padding: 20px;
  margin: 10px;
  background: #fff;
  border-radius: 8px;
}
footer {
  text-align: center;
  padding: 10px;
  background: #2c2c2c;
  color: #fff;
  margin-top: 20px;
}