title: Parallax effect with CSS transition
body: <p>Is it possible to make parallax effect of background image with css transitions? Parallax should be slower than scrolling, so something do slowing is needed - is it possible to do it with css? Or if not, how best to do it with js/jquery?</p>
  
  <p>I care about best performance script, because my webpage is little overloaded.</p>
  
  <p>Could someone tell or show how to do it? I will be very grateful.</p>