body {
  background-color: black;
  color: white;
  background-position:  center center;
  background-repeat: no-repeat;
}
a.nav:link {font-family: Dejavu sans; font-weight: bold; color: white; text-decoration: none; }

a.nav:visited {color: white; text-decoration: none; }
a.nav:hover {color: gray; text-decoration: underline; }
a.nav:active {color: blue; }