<link rel="stylesheet" href="css/master.css" type="text/css" media="screen" charset="utf-8">

<div class='wrap'>
  <img src='images/test_image.png' alt='Test image' />

  <div class='overlay'>
    <p>
      Some blurb about your<br />
      dumb image
    </p>
  </div>
</div>