function isFullScreen() {
	return (document.fullScreenElement && document.fullScreenElement !== null) || document.mozFullScreen || document.webkitIsFullScreen;
}

function requestFullScreen(element) {
	if (element.requestFullscreen)
		element.requestFullscreen();
	else if (element.msRequestFullscreen)
		element.msRequestFullscreen();
	else if (element.mozRequestFullScreen)
		element.mozRequestFullScreen();
	else if (element.webkitRequestFullscreen)
		element.webkitRequestFullscreen();
}

function exitFullScreen() {
	if (document.exitFullscreen)
		document.exitFullscreen();
	else if (document.msExitFullscreen)
		document.msExitFullscreen();
	else if (document.mozCancelFullScreen)
		document.mozCancelFullScreen();
	else if (document.webkitExitFullscreen)
		document.webkitExitFullscreen();
}

function toggleFullScreen(element) {
	if (isFullScreen())
		exitFullScreen();
	else
		requestFullScreen(element || document.documentElement);
}