function display() {
    frame = document.getElementById("promocje");
  if(hidden)
    frame.style.visibility='hidden';
  else {
    top=document.body.clientHeight-250+document.body.scrollTop;
    left=document.body.clientWidth-192+document.body.scrollLeft;

    frame.style.top=top;
    frame.style.left=left;

    frame.style.visibility='visible';
  }
};

var xoffset;
var yoffset;
var hidden = true;
var started = false;

function afterScroll() {
  x = window.scrollX;
  y = window.scrollY;
  if(xoffset == null || yoffset == null || xoffset != x || yoffset != y) {
    xoffset=x;
    yoffset=y;
    show();
  }
};

function show() {
  hidden = !started;
  display();
};

function startShow() {
  started=true;
  window.onresize=display;
  window.onscroll=display;
  show();
};

function hide() {
  hidden = true;
  display();
};