I have a site and I wanted to change it's background. I want to put a background on top and bottom.

Here is the CSS code:

div.bg_top {
  background-image: url('bg_top.jpg');
  background-repeat: no-repeat;
  background position: top center;
}

div.bg_bottom {
  background-image: url('bg_bottom.jpg');
  background-repeat: no-repeat;
  background position: bottom center;
}

HTML code:

<div class="bg_top">
  <div class="bg_bottom">
    Content Here.
  </div>
</div>

is that correct?