title: How to put image as background in Hero Unit?
body: <p>So far I've got this in my css:</p>
  
  <pre><code>hero-unit {
          background-image: myark.jpg;    
  }
  </code></pre>
  
  <p>Seems pretty obvious but it doesn't work. </p>
  
  <pre><code>.hero_unit{
             }
  </code></pre>
  
  <p>doesn't work either. Sorry. I am new to this if you couldn't tell. </p>