body { margin-left: 5%; margin-right: 5%;
        font-family: sans-serif,Arial, Helvetica;
      }

   H1, H2, H3, H4  {color:blue;
                    font-family: sans-serif;
                   }

   pre { font-family: monospace; background: lightblue;}

    a {text-decoration: none; }
    a:link {text-decoration: none; Color: blue;}
    a:visited  { color: blueviolet; text-decoration: none;}
    a:hover {color: green; text-decoration: none}