body {
  margin: auto;
  width: 750px;
}

nav ul {
  list-style-type: none;
  margin: 0;
  padding: 0;
  overflow: hidden;
  background-color: #333;
}

nav li {
  float: left;
}

nav li a {
  display: block;
  color: white;
  text-align: center;
  padding: 14px 16px;
  text-decoration: none;
}

nav li a:hover {
  background-color: #111;
}

main {
  padding: 10px 20px;
}

.alert {
  position: relative;
  padding: 0.75rem 1.25rem;
  margin-bottom: 1rem;
  border: 1px solid transparent;
  border-radius: 0.25rem;
  color: #004085;
  background-color: #cce5ff;
  border-color: #b8daff;
}

.error {
  color: #721c24;
  background-color: #f8d7da;
  border-color: #f5c6cb;
}

img {
  max-width: 100%;
}

footer {
  font-size: 13px;
  color: #888;
  border-top: 1px solid #eee;
  margin-top: 25px;
  text-align: center;
  padding: 20px;
}
