function addEvent(obj,evType,fn){if(obj.addEventListener){obj.addEventListener(evType,fn,true);return true;}else if(obj.attachEvent){var r=obj.attachEvent("on"+evType,fn);return r;}else{return false;}}
function removeEvent(obj,evType,fn,useCapture){if(obj.removeEventListener){obj.removeEventListener(evType,fn,useCapture);return true;}else if(obj.detachEvent){var r=obj.detachEvent("on"+evType,fn);return r;}else{alert("Handler could not be removed");}}
function getViewportHeight(){if(window.innerHeight!=window.undefined)return window.innerHeight;if(document.compatMode=='CSS1Compat')return document.documentElement.clientHeight;if(document.body)return document.body.clientHeight;return window.undefined;}
function getViewportWidth(){if(window.innerWidth!=window.undefined)return window.innerWidth;if(document.compatMode=='CSS1Compat')return document.documentElement.clientWidth;if(document.body)return document.body.clientWidth;return window.undefined;}