function setZoom(img, dir, width, height, delay, zIndex) {
  setTimeout(function() {
    if (img.dir==dir) {
      img.style.width=width;
      img.style.height=height;
      
      img.style.zIndex=zIndex;
      img.parentNode.parentNode.style.zIndex=zIndex;
    }
  }, delay);
}


function larger(img) {
  img.dir='rtl';
  
  
  wNow=100;
  hNow=69;
  wTarget=200;
  hTarget=137;
  
  now=0;
  for (i=now+1; i<=10; i++) {
    w=(wNow+i*((wTarget-wNow)/10)) +'px';
    h=(hNow+i*((hTarget-hNow)/10)) +'px';
    setZoom(img, 'rtl', w, h, 20*(i-now), i);
  }
}


function smaller(img) {
  img.dir='ltr';

  wNow=200;
  hNow=137;
  wTarget=100;
  hTarget=69;
  
  now=10;
  for (i=now; i>=0; i--) {
    w=(wTarget+i*((wNow-wTarget)/10)) +'px';
    h=(hTarget+i*((hNow-hTarget)/10)) +'px';
    setZoom(img, 'ltr', w, h, 20*(now-i),i);
  }
}