title: Adsense based on view port
body: <p>I am about to launch a responsive website which will have Adsense in it. Since the website is responsive; I am expecting to have different set of Adsense banners to address the correct banner according to screen size.</p>
  
  <p>What is the best approach taken these days to achieve this? Does it rely on Javascript, or simply on CSS like the idea behind responsive (for example resizing the banner's size to fit in the content area).</p>
  
  <p>Lastly, does Adsense have a feature yet to build the same banner spot for several devices, and deliver the correct banner based on the view port?</p>
  
  <p>Thanks a lot.</p>