Resizing background image

Hi everyone,

I’m trying to resize this background image that my text sits in front of:
http://www.drivewaydealsbookstore.com

The code is:

.article-corps {
	position:relative;
	background:url(images/article_sprite.png) repeat-y;
	background-position:-683px 0;
	margin-left:30px;
	padding:13px 43px 0 50px;
	line-height:20px;
	overflow:hidden;
}

I tried adding a code like “width: 130%” but nothing works. Please help, I’ve already spent 5 hours on this and am considering using a new template. I purposely changed the text width and want the background image to match.