html {
  background-color:grey;
  font-family:Exo;
}

.header {
  position:relative;
  margin-bottom:50px;
}

.pages {
  position:relative;
  display:inline-block;
  background-color:black;
  padding:10px 20px 0px 20px;
  border-radius: 10px 10px 0 0;
  margin:5px 5px 0px 5px;
}

.linkbar {
  border-bottom:3px solid black;
}

.footer {
  border-top:1px solid black;
  clear:both;
  bottom:0px;
  width:100%;
  position:fixed;
  background:grey;
}

a:hover {
  text-decoration:none;
}

.subheader {
  margin-top:-40px;
  margin-bottom:10px;
}

.displayex {
  width:50%;
  height:auto;
}

.displayhead{
  border:1px solid black;
  font-weight: bold;
}

html {
  background-color:grey;
  font-family:Exo;
}
body{
  margin: 5%;
}

.header {
  position:relative;
  margin-bottom:50px;
}

.pages {
  position:relative;
  display:inline-block;
  background-color:black;
  padding:10px 20px 0px 20px;
  border-radius: 10px 10px 0 0;
  margin:5px 5px 0px 5px;
}

.linkbar {
  border-bottom:3px solid black;
}

.footer {
  border-top:1px solid black;
  clear:both;
  bottom:0px;
  width:100%;
  position:fixed;
  background:grey;
  margin-top: 3%;
}

a:hover {
  text-decoration:none;
}

.subheader {
  margin-top:-40px;
  margin-bottom:10px;
}

.displayex {
  width:50%;
  height:auto;
}

.displayhead{
  border:1px solid black;
  font-weight: bold;
}

Add margins to improve readibility
Add margins to improve readibility

The blog post on Arrays and Hashes needs margins to make it easier to read.  The post has a great analogy so show it off.