zepto-jquery-cdn-fallback.html

<!-- Load either Zepto or jQuery, as necessary, from a CDN with a local fallback -->
<script>
  document.write('<script src="//cdnjs.cloudflare.com/ajax/libs/' +
  ('__proto__' in {} ?
    'zepto/1.0/zepto.min' :
    'jquery/1.10.2/jquery.min')
  + '.js"><\/script>')
</script>
<script>
  window.$ || document.write('<script src="js/vendor/' +
    ('__proto__' in {} ? 'zepto.min' : 'jquery-1.10.2.min')
  + '.js"><\/script>')
</script>