body {
  background-color: gold;
  height: 100%;
}



header {
  background-color: red;
  min-height: 6em;
}

nav {
  background-color: darkred;
  min-height: 3em;
}



main {
  background-color: green;
  //min-height: 20em;
}

section {
  background-color: lightblue;
  width: 60%;
  float: left;
}

main header {
  background-color: lightgreen;
  min-height: 3em;
}

article {
  background-color: white;
}

main footer {
  background-color: lightgreen;
  min-height: 3em;
}

aside {
  background-color: brown;
  width: 30%;
  float: right;
  min-height: 20em;
}



footer {
  background-color: blue;
  clear: both;
  min-height: 6em;
}