document.observe('mousemove', function(e) {
	var current_box = Event.findElement(e, '.block');
	if(current_box) {
		$$('.block').each(function(block) {
			if(block.id!=current_box.id) {
				block.hide();
			}
		});
	}
	x = Event.pointerX(e);
	y = Event.pointerY(e);
	if(y<400 || y>584) {
		hideBlocks();
	}
})
function hideBlocks() {
	var blocks = $$('.block');
	for(var i=0; i<blocks.length; i++) {
		blocks[i].style.display = 'none';
	}
}