function closeMenu(e) {
  var sidebar = document.querySelectorAll("#sidebar")[0];
  var input = sidebar.querySelectorAll("input.menu-toggle")[0];
  if (e.keyCode == 27 || (e.type == 'click' && e.target.closest('#sidebar') === null)) {
    if (input.checked) {
      input.checked = false;
    }
  }
}
function addListenersOnLoad() {
  var sidebar = document.getElementById("sidebar");
  document.addEventListener("click", closeMenu, false);
  document.addEventListener("keyup", closeMenu, false);
}
document.addEventListener("DOMContentLoaded", addListenersOnLoad, false);