Em-driven layout example

CSS

#example04 #header {
  height: 50px;
  width: 44em;
  background-color: #999;
  margin-bottom: 10px;
}

#example04 #nav {
  float: left;
  width: 11em;
  height: 150px;
  background-color: #ccc;
  margin-bottom: 10px;
}

#example04 #content {
  margin-left: 13em;
  height: 150px;
  width: 31em;
  background-color: #ccc;
}

#example04 #footer {
  clear: both;
  height: 50px;
  width: 44em;
  background-color: #999;
  margin-bottom: 10px;
}