body {
  color: black;
  background-color: white;
  margin-top: 40px;
  margin-bottom: 40px;
  margin-left: 10%;
  margin-right: 10%;
  font-family: Tahoma, Helvetica, Sans-Serif;
}

h1 {
  color: gray;
  background-color: yellow;
  font-size: 200%;
  font-weight: bold;
  text-align: left;
}

h2 {
  color: yellow;
  background-color: gray;
  font-size: 125%;
  font-weight: normal;
  font-style: italic;
  text-align: left;
}

li {
  margin-top: 0.5ex;
}

code {
  color: navy;
}

pre {
  color: black;
  background-color: rgb(240,240,240);
  border: 1px solid navy;
  padding: 1em;
  font-size: 90%;
}