How do I change background to image Hot Ecommerce?

I have purchased the Hot Ecommerce Joomla 1.5 template and I am currently using style 5. How do I go about changing the grey background to a tiled image? What css code do I change? Anyone's help in immensely appreciated!

Open:
templates\hot_ecommerce\styles\style5.php

and change variable values.

I appreciate your response. I have located style5.php and altered some colors but have no idea where to add or change a variable for a tiled background image. Would it be possible for you to tell me what to put in the file to accomplish this? Normally I'd be able to figure it out with the css file but it isn't writable. Here is an example of the a background: " tshirtmassacre.com/images/tshirtmassacre-background.jpg "

As for style5.php I can't pinpoint which variable is for the grey background if it is even listed at all. I have gone through each color code and can't seem to pinpoint it. I'm not sure if you can help me but if you can it is very appreciated!

Thanks

Here's the php info for my style5.php:

<?php

$bodyText = "#666666";
$linkColor = "#A8B1B8";
$backgroundColor = "#222";
$headerBgImage = "5";
$contentBg = "#000";
$logoTextColor = "#6D98AB";
$sloganTextColor = "#A8B1B8";
$callText = "#FFFFFF";
$menuAnimationEffect = "show(400)";
$topMenuText = "#00275E";
$topMenuHoverText = "#FFFFFF";
$submenuBg = "#00275E";
$submenuText = "#FFFFFF";
$submenuTextHover = "#FFEB00";
$mainMenuText = "#FFFFFF";
$mainMenuHoverText = "#FF7902";
$mainMenuTextActive = "#FF7902";
$componentHeadingText = "#6D98AB";
$headingText = "#6D98AB";
$headingHoverText = "#6D98AB";
$columnFirstWord = "#FEB729";
$columnHeading = "#FEB729";
$columnText = "#FFF";
$modulesHeadingBgStart = "#00275E";
$modulesHeadingBgEnd = "#000000";
$modulesBg = "#163054";
$modulesBorder = "#000";
$breadcrumbsColor = "#6D98AB";
$vmTabColor = "#666666";
$vmTabBgStart = "#D3D1D1";
$vmTabBgEnd = "#E3E5E7";
$vmTabActiveColor = "#FFFFFF";
$vmTabActiveBgStart = "#4b759a";
$vmTabActiveBgEnd = "#88a8cc";
$footerBg = "#163054";
$footerModuleHeading = "#88a8cc";
$footerText = "#88a8cc";
$copyrightText = "#88a8cc";

?>

That image for your style is:
/templates/hot_ecommerce/images/bg5.png