function showTxt(tagId) {
  var tag = document.getElementById(tagId);
  var tag2 = tag.childNodes[0];
  var span = tag.getElementsByTagName('span')[0];
  span.style.display = "block";

}

function hideTxt(tagId) {
  var tag = document.getElementById(tagId);
  var tag2 = tag.childNodes[0];
  var span = tag.getElementsByTagName('span')[0];
  span.style.display = "none";
}