.main {
  display: flex;
  max-width: 900px;
  margin: 0 auto;
  color: #222;
}
.navbar {
  padding: 32px;
  font-family: Verdana, Geneva, Tahoma, sans-serif;
}
.navbar ul {
  margin: 0;
  padding: 0;
}
.nav-link {
  list-style: none;
  margin: 8px;
  padding: 8px 16px;
  background-color: lightgray;
  font-size: large;
}
.nav-link--current {
  background-color: lightblue;
}

.article {
  font-family: "Times New Roman", Times, serif;
}
.article h1, h2 {
  font-family: Arial, Helvetica, sans-serif;
  color: #444;
}
.article blockquote {
  margin: 8px 0;
  padding: 2px 8px;
  border-radius: 8px;
  background-color: #eee;
  font-style: italic;
  color: #444;
}
.article pre {
  background-color: #222;
  color: yellow;
  padding: 16px;
}