CSS to overlay centered text on a background image : <p>I'm not an html/css guy but the guy who usually does this quit so it fell into my lap.</p>

<p>I have a page where there is a background image to fill the entire page. I found some sample css online to do this:</p>

<pre><code>html {
        background: url(background.png) no-repeat center center fixed;
        -webkit-background-size: cover;
        -moz-background-size: cover;
        -o-background-size: cover;
        background-size: cover;
    }
</code></pre>

<p>What I want to do now is overlay some text on this such that it appears at the centered at the bottom of the page (not right at the bottom, maybe 50 px up from bottom). I tried a bunch of things but can't seem to get it quite right.</p>
