<?xml version="1.0"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="cs" lang="cs">
<head>
   <title>Test</title>
</head>
<body>
<style type="text/css">
p {
  border: medium solid purple;
  }
p.center {
  text-align: center;
}
p.mozcenter {
  text-align: -moz-center;
}
table.center {
  margin-left: auto;
  margin-right: auto;
}
table {
  border: medium solid green;
  padding-right: 2em;
  padding-left: 2em;
}
caption.center { margin-left: auto;
  margin-right: auto;
}
caption { border: medium solid orange;
  padding-right: 1em;
  padding-left: 1em;
}
</style>
<p align="center"><table><caption>cap</caption><tr><td>Centered<br>OK</td></tr></table></p>

<p><table class="center"><caption class="center">cap</caption><tr><td>Centered<br>SHIFT</td></tr></table></p>

<p class="mozcenter"><table><caption>cap</caption><tr><td>Centered<br>NOSTD</td></tr></table></p>

</body>
</html>