// Element.prototype.classList polyfill
// developed by thednp
// license MIT

(function(){
   if( !Element.classList ) {
    Element.classList = function(){
      var element = this, className = 'className', add = 'add', remove = 'remove', contains = 'contains',
          classLIST = element[className].split(/\s/);

      // methods
      classLIST[add] = function(classNAME){
        return function(){
          var classINDEX = classLIST.indexOf(classNAME);
          if (classINDEX<0) {
            classLIST.push(classNAME);
            element[className] = classLIST.join(' ');
          }
        }.call();
      };
      classLIST[remove] = function(classNAME){
        return function(){
          var classINDEX = classLIST.indexOf(classNAME);
          if (classINDEX>-1) {
            classLIST.splice(classINDEX,1);
            element[className] = classLIST.join(' ');
          }
        }.call();
      };
      classLIST[contains] = function(classNAME){
        return classLIST.indexOf(classNAME) > -1;
      };
      return classLIST;
    };
  }
})();