p {
  margin: 10px 0;
}

body {
  max-width: 550px;
  margin: auto;
  padding: 6px 8px;
  background-color: #111;
  color: #ddd;

  font-size: 18px;
}

.text-center {
  text-align: center;
}

a {
  color: lightskyblue;
}
a:visited {
  color: lightseagreen;
}