title: Responsive E-commerce site? One version vs Multi-version
body: <p>Our company decide to not support IE7-8 which is super good new year news And I want to apply zurb-foundation5 css to our existing medium size e-commerce site so mobile user can have better UX/UI experience. However, I realize that many elements such as html or asp needs to be restructured and duplicated if I want to make the site display well on mobile. This would cause slow speed of site experience and perhaps even some other issues. However, If I made separate site for mobile, I would have to maintain two sites!!</p>
  
  <p>My question is 
     What are the pros and cons of making a separate site for mobile vs. merging responsive css to current site and modify, rewrite, duplicate, move around html/elements?</p>