h1, h2, h3, h4 { 
  font-weight: bold;
}

a:link:hover, a:visited:hover {
  color: darkred;
  background-color: yellow;
}

body {
  background-color: white;
  color: black;
  margin-left: 15%;
  margin-right: 15%;
}

code, tt {
  font-family: monospace;
  font-weight: bold;
  font-style: normal;
}

pre {
  background-color: gainsboro;
  font-family: monospace;
  font-weight: bold;
  font-style: normal;
  white-space: pre;
  margin-left: 40pt;
  margin-right: 40pt;
  padding: 10pt;
}

pre.src {
  background-color: #eeeeee;
}