function (el) {
  var className = el.className
  var listClass = className.split(' ')
  this.classList = listClass
  this.el = el
}
function (el) {
  var className = el.className
  var listClass = className.split(' ')
  this.classList = listClass
  this.el = el
}
function ( el ) { var className = el . className var listClass = className . split ( ' ' ) this . classList = listClass this . el = el }
new object function for unsupport classList
new object function for unsupport classList