Simple way of detecting and adding body-classes for mobile devices. Classes added: 'mobile', 'iphone', 'android'

mobilecss.js

(function(d, l, c) {
  while(c=l.pop()){
    if(navigator.userAgent.match(new RegExp(c, 'i'))){
      d[c]=!0;
      d.documentElement.className+=' '+c;
    }
  }
}(document, ['iphone', 'mobile', 'android']));