title: Unexplained margin at top of page
body: <p>On my client's website <a href="http://opcstm.org/" rel="nofollow">opcstm.org</a> every browser I've tried (Chrome, Firefox, Internet Explorer) renders a margin of about 16px at the top of each page except the homepage.</p>
  
  <p>For example, compare the homepage to the <a href="http://opcstm.org/contact-us-2/" rel="nofollow">Contact Us page</a>. On the Contact Us page you will see that the logo, the entire header element, and the entire page is separated from the top of the browser window by about 16x of margin.</p>
  
  <p>I've used browser developer tools to inspect the first three elements in the HTML code (body, div.site-container, header.site-header) and none of them have top margin or top padding specified.</p>
  
  <p>I'm stumped! Can you help?</p>