function closeExpanded() {
    var navbarDiv = document.getElementById("navbar");
    var navbar_ol = navbarDiv.getElementsByTagName("ol");
    for (i=0; i<navbar_ol.length; i++) {
        if (navbar_ol[i].style.display == "list-item") {
           navbar_ol[i].style.display = "none";
        }
    }
}
            
function toggle(liletter) {
    // Close all expanded "ordered-list" items
    closeExpanded();

    var x=document.getElementById(liletter);

    if (x.style.display == "none") {
        x.style.display = "list-item";
    } else {
        x.style.display = "none";
    }
}