function getWidth() {
  if (window.innerWidth) { widthAvail = window.innerWidth; }
  else if (document.documentElement && document.documentElement.clientWidth) { widthAvail = document.documentElement.clientWidth; }
  else if (document.body) { widthAvail = document.body.clientWidth; }
  return widthAvail;
}

function getHeight() {
  if (window.innerWidth) { heightAvail = window.innerHeight; }
  else if (document.documentElement && document.documentElement.clientWidth) { heightAvail = document.documentElement.clientHeight; }
  else if (document.body) { heightAvail = document.body.clientHeight; }
  return heightAvail;
}