body {
  font-family: Arial, sans-serif;
  max-width: 900px;
  margin: 1em auto;
  padding: 1em;
  background: #f4f4f4;
  color: #222;
}

header, footer {
  text-align: center;
  margin-bottom: 1em;
  background-color: #e3e3e3;
  padding: 0.5em;
  border-radius: 5px;
}

nav ul {
  list-style-type: none;
  display: flex;
  justify-content: center;
  gap: 1.5em;
  padding: 0;
  margin-bottom: 1em;
}

nav ul li a {
  text-decoration: none;
  color: #005a87;
  font-weight: bold;
}

nav ul li a:hover {
  text-decoration: underline;
}

main {
  background: #fff;
  padding: 1em;
  border-radius: 5px;
  box-shadow: 0 0 8px #ccc;
}