function toggleToc(event) {
	icon = event.target;
	iconCl = icon.classList;
	if (icon.getAttribute('aria-expanded') == "true") {
		iconCl.remove('fa-chevron-up');
		iconCl.add('fa-chevron-down');
		icon.setAttribute('aria-expanded', false)
	} else {
		iconCl.remove('fa-chevron-down');
		iconCl.add('fa-chevron-up');
		icon.setAttribute('aria-expanded', true)
	}
	var li = icon.parentElement;
	var cl = li.querySelector('ul').classList;
	if (cl.contains('hidden-toc-element')) {
		cl.remove('hidden-toc-element');
	} else {
		cl.add('hidden-toc-element');
	}
}

function keyDownToggleToc(event) {
	if (event.isComposing || event.keyCode == 229) {
		return;
	}
	if (event.keyCode == 13 || event.keyCode == 32 || event.keyCode == 37 || event.keyCode == 38 || event.keyCode == 39 || event.keyCode == 40) {
		event.preventDefault();
		toggleToc(event);
	}
}

document.querySelectorAll('.sectlevel1 > * > icon').forEach(sectLevel1 => {
	sectLevel1.addEventListener('click', toggleToc);
	sectLevel1.addEventListener('keydown', keyDownToggleToc);
})