Collapse accordian

[JustAnotherNewbie]

I have used the script for creating an accordion from w3Schools .  I would like to add a button somwhere on the page that would collapse all that are open. Even if it is just a reload of the page which would work.

    <script>
        var acc = document.getElementsByClassName("accordion");
        var i;

        for (i = 0; i < acc.length; i++) {
            acc[i].addEventListener("click", function() {
                this.classList.toggle("active");
                var panel = this.nextElementSibling;
                if (panel.style.display === "block") {
                    panel.style.display = "none";
                } else {
                    panel.style.display = "block";
                }
            });
        }

    </script>

Please help.  I am definitely a newbie.

 

Linda