title: change background-image opacitiy in sections
body: <p>I am trying to remove transparency from the background-image of a section used in a web paged based on twitter bootstrap css but I can't see how to do that.</p>
  
  <p>I have tried </p>
  
  <pre><code>.section{
    opacity:1;
  }
  </code></pre>
  
  <p>but it doesn't work</p>