Ledix

document.getElementById('hider').onclick = function() {
  document.getElementById('config-btn').classList.toggle('hidden');
}

.hidden {
  display: none;
}

document.getElementById('hider').onclick = function() {
	var el = document.getElementById('config-btn');
  el.style.display === 'none' ? el.style.display = 'initial' : el.style.display = 'none';
}