// a key map of allowed keysvar allowedKeys ={37:'left',38:'up',39:'right',40:'down',65:'a',66:'b'};// the 'official' Konami Code sequencevar konamiCode =['up','up','down','down','left','right','left','right','b','a'];// a variable to remember the 'position' the user has reached so far.var konamiCodePosition =0;// add keydown event listener document.addEventListener('keydown',function(e){// get the value of the key code from the key mapvar key = allowedKeys[e.keyCode];// get the value of the required key from the konami codevar requiredKey = konamiCode[konamiCodePosition];// compare the key with the required keyif(key == requiredKey){// move to the next key in the konami code sequence konamiCodePosition++;// if the last key is reached, activate cheatsif(konamiCodePosition == konamiCode.length){ activateCheats(); konamiCodePosition =0;}}else{ konamiCodePosition =0;}});function activateCheats(){ document.body.style.backgroundImage ="url('images/cheatBackground.png')";var audio =newAudio('audio/pling.mp3'); audio.play(); alert("cheats activated");}