CSS styling of Joomla RokEcwid e-commerce plugin on website

I need the RokEcwid plugin in Joomla styled using CSS to match the colour schemes and look and feel of the rest of my website. It is already implemented in the website but I have not been able to re-style it effectively. All the pages that feature in this - store front, category, listing and checkout as well as mini-card module - will need to be styled. What I would like to achieve can be seen in the Mercado template on Rocketthemes. Winning bidder will be given my website URL and admin details and will need to style this plugin using their own initiative to come up with a look that fits in with the rest of the website.