body {
  color: black;
  background: #ffffff;
  margin-left: 10%;
  margin-right: 10%;
}
a:link { color: #0000ff; text-decoration: none }
a:visited { color: #0000ff; text-decoration: none }
a:hover { color: #0000ff; text-decoration: underline }
a:active { color: #ff0000; text-decoration: none }
div.colored-bg {
  background: rgb(177,203,226);
  padding: 0.5em;
  border: none;
  }
code { background: #ffffaa; font-size: larger }