title: HTML5 input validation doesn't work in IE8
body: <p>Hello kind people of the internet,
  I've been hacking at this for a while...and have seen several similar postings, but I can't seem to figure this out:</p>
  
  <p>The HTML5 input field validation CSS works in Firefox, Chrome...but alas, not in IE8...and much of my target audience will be using IE8.</p>
  
  <p>...and yes: I'm using Modernizr, and I used Initializr to get the page template and CSS...I'm a bit confused why I can't get things working properly in IE8.</p>
  
  <p>Here's a link to my test page:
  <a href="http://www.msa.saccounty.net/utilitybilling/streetview/TestHTML5pagev6.aspx">Test html5 page</a></p>
  
  <p>The input field is red before proper entry, then validation simply turns green when input a valid account number, such as:
  50011111111</p>
  
  <p>The HTML5 code is as follows:</p>
  
  <pre><code>&lt;label for="account"&gt;Account Number: &lt;/label&gt; 
  &lt;input id="account" name="inputAccount" 
    placeholder="input billing account number" 
    pattern="/(^500)|^\d{11}" 
    required
    autofocus
    type="text"/&gt;
  </code></pre>
  
  <p>Any suggestions on what is probably a fairly simple thing to fix would be mucho appreciated!</p>