using panels and .ui-page-background possible?

using panels and .ui-page-background possible?

Hello guys!

Looks like no one has an idea for my problem: As soon as i insert panels to my page, my background-image disappears!

BG-Image (CSS):

.ui-page {
  background-image:url("../images/bg.png"); -> 50x50px image
  background-repeat:repeat;
}

Placing Panels into site:

<div id="page" data-role="page" data-theme="a">

<div id="header" data-role="header" data-position="fixed" data-tap-toggle="false" data-theme="c">
      ...
</div>

<div class="menu" data-role="panel" data-position-fixed="true" data-position="left" data-display="reveal">
      <ul data-role="listview" data-theme="c">
...
      </ul>
</div>
<div class="favs" data-role="panel" data-position-fixed="true" data-position="right" data-display="reveal">
      <ul data-role="listview" data-theme="c">
            ...
      </ul>
</div>


When i delete the panel-divs, my background image is shown, but if inserted as above (tried different positions in the markup), the background-image is not shown any more, but the color i defined with the theme-roller instead!

NOTE: I am using class= instead of id= because this works fine to open with swiping gestures! But this has no effect on the background-issue. I tried the id-variant too!

I spent now a couple of days trying, but i don't know what to change, so that my background will not disappear! Pleas give me some hint!