CSS rollover - background image wont center

I have a rollover top menu. Im trying to get it so my background image (17px x 13px) appears on hover in the 开发者_JS百科center. I've tried all the background css attributes and nothing seems to work. Am I going about this the wrong way?

Here is my CSS:

#navlist a:hover
{
    color: #fff;
    background-color: #b2b85c;
    text-decoration: none;
    background-image: url(Images/pointer.jpg);
    background-position: center bottom;
    background-attachment: fixed;
}

Here is a link to the page.

http://kerrydean.ca/Grey%20River/greyRiverTemplate2.html

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By navigation I assume you mean the top menu.

Try adding background-repeat: no-repeat; to your CSS rule for #navlist a:hover