top.posuv = 0;
top.odsadit = 250;
top.nahrano = false;

function posun(objekt) { 
	top.odsadit -= 50;
	objekt.style.left = top.odsadit+"px";
	if (top.odsadit <= 0) {
		clearInterval(top.posuv);
		top.posuv = 0;
	}
}