/* main.js */

//cross browser event registration
function addEvent(element,event,call,bubble) {
  if (window.addEventListener) {
    element.addEventListener(event,call,bubble);
  }
  else if (window.attachEvent) {
    element.attachEvent('on'+event,call);
  }
}
//cross browser event unregistration
function removeEvent(element,event,call,bubble) {
  if (window.removeEventListener) {
    element.removeEventListener(event,call,bubble);
  }
  else if (window.detachEvent) {
    element.detachEvent('on'+event,call);
  }
}