I have a very simple website where I have a picture of my wife and I for the last 19 years that we’ve been together. A picture per month. It loads using lazy load which works great. I added anchor links (is that what they’re called?) so you can skip from year to year from the header. But imagine now I have 19 links up there. Friend of mine told me I should look into dropdown menu. I was able to find an example online and it works. But now it gives me 19 links vertically instead of horizontally. So I thought I would break it down into multiple subcategories. 2020-2024, 2010-2019 and 2005-2009. I got it “working” individually, but as soon as I enable all three, only the last one shows. What am I missing here? Please note I have very little css/js/html experience. I can follow directions well but I don’t know what’s natively in the language that should be obvious to someone with more experience.

Here is the relevant portions of the page. As I said above, I can get each of the three subcategories to work, but not all three at once.

CSS

<style>
/* Dropdown Button */
.dropbtn {
  background-color: white;
  color: black;
  padding: 16px;
  font-size: 16px;
  border: none;
  cursor: pointer;
  box-shadow: 0px 4px 4px 0px rgba(0,0,0,0.2);
}

/* Dropdown button on hover & focus */
.dropbtn:hover, .dropbtn:focus {
  background-color: white;
  box-shadow: 0px 8px 16px 0px rgba(0,0,0,0.2);
}

/* The container <div> - needed to position the dropdown content */
.dropdown {
  position: relative;
  display: inline-block;
}

/* Dropdown Content (Hidden by Default) */
.dropdown-content {
  display: none;
  position: absolute;
  background-color: #f1f1f1;
  min-width: 160px;
  box-shadow: 0px 8px 16px 0px rgba(0,0,0,0.2);
  z-index: 1;
}

/* Links inside the dropdown */
.dropdown-content a {
  color: black;
  padding: 12px 16px;
  text-decoration: none;
  display: block;
}

/* Change color of dropdown links on hover */
.dropdown-content a:hover {background-color: #ddd;}

/* Show the dropdown menu (use JS to add this class to the .dropdown-content container when the user clicks on the dropdown button) */
.show {display:block;}
</style>

JavaScript

<script>
/* When the user clicks on the button,
toggle between hiding and showing the dropdown content */
function doDropdown() {
  /*document.getElementById("myDropdown").classList.toggle("show");*/
  document.getElementById("dropDown2020").classList.toggle("show");
  document.getElementById("dropDown2010").classList.toggle("show");
  document.getElementById("dropDown2000").classList.toggle("show");
}

function showDecade2020(){
    document.getElementById("myDropdown2020").classList.toggle("show");
}

function showDecade2010(){
    document.getElementById("myDropdown2010").classList.toggle("show");
}

function showDecade2000(){
    document.getElementById("myDropdown2000").classList.toggle("show");
}

// Close the dropdown menu if the user clicks outside of it
window.onclick = function(event) {
  if (!event.target.matches('.dropbtn')) {
    var dropdowns = document.getElementsByClassName("dropdown-content");
    var i;
    for (i = 0; i < dropdowns.length; i++) {
      var openDropdown = dropdowns[i];
      if (openDropdown.classList.contains('show')) {
        openDropdown.classList.remove('show');
      }
    }
  }
}
</script>

HTML

<div class="dropdown">
          <button onclick="doDropdown()" class="dropbtn">Jump to a specific year...</button>                  
          <div id="dropDown2020" class="dropdown-content">
            <button onclick="showDecade2020()" class="dropbtn">2020-2024</button>
            <div id="myDropdown2020" class="dropdown-content">
            <a href="#2024">2024</a>
            <a href="#2023">2023</a>
            <a href="#2022">2022</a>
            <a href="#2021">2021</a>
            <a href="#2020">2020</a>
            </div>
          </div>
          <div id="dropDown2010" class="dropdown-content">
            <button onclick="showDecade2010()" class="dropbtn">2010-2019</button>
            <div id="myDropdown2010" class="dropdown-content">
            <a href="#2019">2019</a>
            <a href="#2018">2018</a>
            <a href="#2017">2017</a>
            <a href="#2016">2016</a>
            <a href="#2015">2015</a>
            <a href="#2014">2014</a>
            <a href="#2013">2013</a>
            <a href="#2012">2012</a>
            <a href="#2011">2011</a>
            <a href="#2010">2010</a>
            </div>
          </div>
          <div id="dropDown2000" class="dropdown-content">
            <button onclick="showDecade2000()" class="dropbtn">2005-2009</button>
            <div id="myDropdown2000" class="dropdown-content">
            <a href="#2009">2009</a>
            <a href="#2008">2008</a>
            <a href="#2007">2007</a>
            <a href="#2006">2006</a>
            <a href="#2005">2005</a>
            </div>
          </div>         
        </div>