I have a small design problem in my css, and I'd like to know if someone could check it out for me. The design problem is in the rollover effect of my horizontal navigation. There seems to be some sort of added margin or padding, but I'm having trouble finding the problem in the css. I will paste the code I'm using below, so you can see for yourself. You won't be able to see the problem until you rollover the navigation list items.

HTML:

    <div class="Horiznav">
  <ul>
    <li id="active"><a href="#">Link #1</a></li>
    <li><a href="#">Link #2</a></li>
    <li><a href="#">Link #3</a></li>
    <li><a href="#">Link #4</a></li>
    <li><a href="#">Link #5</a></li>
  </ul>
</div>

CSS:

.Horiznav {
  background: #1F00CA;
  border-top: solid 1px #fff;
  border-bottom: solid 1px #fff;
}
.Horiznav ul {
  font-family: Arial, Helvetica, sans-serif;
  font-weight: bold;
  color: #fff;
  text-Align: center;
  margin: 0;
  padding-top: 5px; padding-bottom: 5px;
}
.Horiznav ul li {
  display: inline;
}
.Horiznav ul li a {
  padding-top: 5px;
  padding-bottom: 5px;
  color: #fff;
  text-decoration: none;
  border-right: 1px solid #fff;
}
.Horiznav ul li a:hover {
  background: #16008D;
  color: #fff;
}
#active a { border-left: 1px solid #fff; }