title: wrapper with opacity and set div on this wrapper without opacity
body: <p>I have wrapper div that has opacity set to 0.75. The problem is that when I place another div it also is transparent.</p>
  
  <p>Here is <strong>HTML</strong>:</p>
  
  <pre><code>&lt;div id="header_wrapper"&gt;
       &lt;div id="header"&gt;
           &lt;div class="logo"&gt;&lt;/div&gt;               
           &lt;ul class="hor_list" id="main_menu"&gt;
              &lt;li&gt;&lt;a href="#"&gt;Home&lt;/a&gt;&lt;/li&gt;
           &lt;/ul&gt;
       &lt;/div&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>CSS:</p>
  
  <pre><code>#header_wrapper {           
      background: black;
      opacity:0.75;
      filter:alpha(opacity=75); /* For IE8 and earlier */         
      height: 82px;
      margin-bottom: 60px;
  }
  </code></pre>
  
  <p>In this case <code>div.logo</code> and <code>ul#main_menu</code> are both transparent and this is a problem. How to stop this?</p>