Tab

function navhide() {
    if (document.getElementById('nav-hide').style.visibility == 'visible') {
        document.getElementById('nav-hide').style.visibility = 'hidden';
    } else {
        document.getElementById('nav-hide').style.visibility = 'visible';
        // To close other tabs
        document.getElementById('settings-menu').style.visibility = 'hidden';
    }
}