stylesheet_flexible_product_listing.css has demo styling set by default. Just delete any properties you don't want.
Code:
th.listingModel {}/*heading elements can be individually controlled like this*/
.productListing-rowheading th {} /*control all heading elements with this*/
.productListing-even td, .productListing-odd td {} /*control all listing elements with this*/
.listingModel {}
.listingName {}
h3.itemTitle {}
.listingDescription {margin: 0.5em 1em 1.5em;}
.listingManufacturer {}
.listingPrice {float: left;} /*demo setup*/
.listingButtonGroup {float: right; width:50%; border-left: 1px solid #999999;} /*demo setup*/
.listingQuantity {text-align: right;}
.listingWeight {text-align: right;}
.listingImage {text-align: center;}
.listingProductImage {}