title: html pattern="[A-Za-z]{50}" is saying valid input is invalid
body: <p>I have a page with some text fields and I would like to restrict user input, so I have used the html5 pattern attribute, like so:</p>
  
  <pre><code>&lt;input name="team_name" type="text" pattern="[A-Za-z]{50}" value="&lt;?php echo $team_name;?&gt;"&gt;
  </code></pre>
  
  <p>This should allow me to enter only letters b/w Aa-Zz for a name, but when I try to enter a <strong>valid</strong> name, it still tells me to match the requested format.
  What am I missing? How come it is always telling me that my input is invalid?</p>