Good day to you all,
here is a question about making a show/hide toggle button instead of two separate button.

Here is my code :

function hide(li) {
       
  if (document.getElementById)
     document.poppedLayer = eval('document.getElementById(li)');
  else if (document.all)
     document.poppedLayer = eval('document.all[li]');
  else
     document.poppedLayer = eval('document.layers[li]');
  document.poppedLayer.style.display = "none";
}

function show(li) {
  if (document.getElementById)
     document.poppedLayer = eval('document.getElementById(li)');
  else if (document.all)
     document.poppedLayer = eval('document.all[li]');
  else
     document.poppedLayer = eval('document.layers[li]');
  document.poppedLayer.style.display = "block";
}

I'm not sure I understand the way your code is set up. (no need for an eval, that is for sure, and the legacy "else if (document.all)" statement is no longer required by today's standards).

What you are asking is very simple:

function toggle(li) {
  var element = document.getElementById(li);
  if(element.style.display == "none")
      element.style.display = "block";
  else
      element.style.display = "none";
}