/** * navigation.js * * Handles toggling the navigation menu for small screens. */ ( function() { var container, toggle, button, menu; container = document.getElementById( 'navigation' ); if ( ! container ) { return; } toggle = document.getElementById( 'menu-toggle' ); if ( ! toggle ) { return; } button = toggle.getElementsByTagName( 'button' )[0]; if ( 'undefined' === typeof button ) { return; } menu = container.getElementsByTagName( 'ul' )[0]; // Hide menu toggle button if menu is empty and return early. if ( 'undefined' === typeof menu ) { button.style.display = 'none'; return; } menu.setAttribute( 'aria-expanded', 'false' ); if ( -1 === menu.className.indexOf( 'nav-menu' ) ) { menu.className += ' nav-menu'; } button.onclick = function() { if ( -1 !== container.className.indexOf( 'toggled' ) ) { container.className = container.className.replace( ' toggled', '' ); button.setAttribute( 'aria-expanded', 'false' ); menu.setAttribute( 'aria-expanded', 'false' ); } else { container.className += ' toggled'; button.setAttribute( 'aria-expanded', 'true' ); menu.setAttribute( 'aria-expanded', 'true' ); } }; } )();