title: CSS: background image on background color
body: <p>I have panel which I colored blue if this panel is being selected (clicked on it). Additionally, I add a small sign (<code>.png</code> image) to that panel, which indicates that the selected panel has been already selected before.</p>
  
  <p>So if the user sees for example 10 panels and 4 of them have this small sign, he knows that he has already clicked on those panels before. This work fine so far. The problem is now that I can't display the small sign and make the panel blue at the same time.</p>
  
  <p>I set the panel to blue with the css <code>background: #6DB3F2;</code> and the background image with <code>background-image: url('images/checked.png')</code>. But it seems that the background color is above the image so you cannot see the sign.</p>
  
  <p>Is it therefore possible to set <code>z-index</code>es for the background color and the background image?</p>