Click a few links on the left...
http://www.logooutpost.com/index.php

After you've been to a few pages there is a gap between the links that have been visited and not visited. I did not write the style sheet and have never come across this problem.

Can anyone see any reason for this?
Code:
.CategoriesBox {
  background: #4443C0;
}
.CategoriesBoxHeading, .CategoriesBoxHeading A, .CategoriesBoxHeading A:link, .CategoriesBoxHeading A:visited, .CategoriesBoxHeading a:hover {
  font-family: "trebuchet ms", helvetica; 
  font-weight: bold; 
  font-size: 12px;  
  color: #ffffff;
  background: url(images/header.gif) fixed no-repeat;
}
.CategoriesBoxHeading A:hover {  
  font-family: "trebuchet ms", helvetica; 
  font-weight: bold; 
  font-size: 12px;  
  color: #ffffff;
  text-decoration: underline;
}
.CategoriesBoxContents, .CategoriesBoxContents a:link,.CategoriesBoxContents a:active, .CategoriesBoxContents a:visited  {
  background: #f5f5f5;
  font-family: Verdana, Arial, sans-serif;
  font-size: 10px;
  color: #363C8A;
}
.CategoriesBoxContents A:hover {
  background: #f5f5f5;
  font-family: Verdana, Arial, sans-serif;
  font-size: 10px;
  color: #363C8A;
  text-decoration: underline;
}