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

header {
  background-color: #333;
  color: #fff;
  padding: 1em;
  text-align: center;
}

header nav ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  justify-content: space-between;
}

header nav ul li {
  margin-right: 20px;
}

header nav a {
  color: #fff;
  text-decoration: none;
}

main {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 2em;
}

section {
  background-color: #f7f7f7;
  padding: 2em;
  margin-bottom: 20px;
  box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
}

h1, h2 {
  color: #333;
}

button {
  background-color: #333;
  color: #fff;
  border: none;
  padding: 10px 20px;
  font-size: 16px;
  cursor: pointer;
}

button:hover {
  background-color: #444;
}

footer {
  background-color: #333;
  color: #fff;
  padding: 1em;
  text-align: center;
  clear: both;
}