CSS background-image using background-position has a glitchy effect
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My site is here:
http://birnamwoodgames.com/index.php

The code that is having the problem is:

    /* footer */
    #footerwrapper {
        height: 225px;
        background-color: #000000;
        background-image: url('../images/footbgRight.jpg');
        background-position: top right;
        background-repeat: no-repeat;
    }

The image shows a weird bar along the bottom, for no reason I can understand. If I position it as just "right", it shows the same bar on the top AND bottom of the image.

Can anyone help me understand why the bar is showing, and what to do about it?