title: Element in td with position:relative overlaps on another position:fixed element
body: <p>I have a mystery to solve: on my web page there's a fixed top panel <strong>div</strong> (similar to gmail's top panel). Below, I have a table with several cells, and the last cell is defined like this:</p>
  
  <pre><code>&lt;td class="col-time"&gt;
      &lt;div title="średnie: 180, maksymalne: 186, minimalne: 142" class="hr-avg"&gt;
          &lt;span&gt;180 (89%) &lt;/span&gt;/ &lt;span class="hr-max"&gt;186 (92%) &lt;/span&gt;
      &lt;/div&gt;
  &lt;/td&gt;
  </code></pre>
  
  <p>The <strong>hr-avg</strong> applies <strong>position:relative</strong> style. </p>
  
  <p>Issue is: when scrolling, table is hidden under that top panel (panel's opacity is 1). But what suprises me is that cell defined with <strong>position:relative</strong> style doesn't hide under panel. Panel &amp; cell's content overlap (it gives the effect like top panel has opacity only for that cell). Could somebody explain that behaviour?</p>
  
  <p>Thanks,Pawel</p>