CSS resizing menu and content background images

I need to have resizable menu and content background images for my site, so both o开发者_开发问答f them get stretched whenever the menu entries are too many, or the contents go outside the borders of the content background. I need vertical stretching.

Could you, please, give me a hint (an actual answer would work as well) or a link to a good example?

Thank you very much in advance!

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You'll probably need to organize a group of elements into something like the following:

html:

<div id="element">
   <div id="elementTop">
     <div id="elementBottom">

     </div>
  </div>
</div>

css:

#element {
  // tileable background image, repeat-y;
}
#elementTop {
  // top, fixed portion of the background image, no-repeat
}
#elementBottom {
  // bottom, fixed portion of the background image, no-repeat, set to:
  background-position: 0 100%;
}