body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  line-height: 1.6;
  max-width: 800px;
  margin: 0 auto;
  padding: 20px;
  color: #333;
}
h1, h2, h3 {
  color: #2c3e50;
}
a {
  color: #3498db;
  text-decoration: none;
}
a:hover {
  text-decoration: underline;
}
pre {
  background-color: #f8f8f8;
  border: 1px solid #ddd;
  border-radius: 3px;
  padding: 10px;
  overflow: auto;
}
code {
  font-family: 'Courier New', Courier, monospace;
}
.nav {
  margin-bottom: 20px;
  padding-bottom: 10px;
  border-bottom: 1px solid #eee;
}
.nav a {
  margin-right: 15px;
}