[Nexus]

Sinie_Nebesa,

var SPACE_KEYCODE=32;
document.onkeydown=function(e){
	var keycode=e.keyCode||e.charCode,
		body=document.body;

	if(keycode!=SPACE_KEYCODE)
		return;
	
	e.preventDefault();
	body.style.overflow=body.style.overflow=='hidden'?'auto':'hidden';
}