<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8"/>
<style type="text/css">
html {
	background-color: #eee;
    padding: 0;
    margin: 0;
}

body {
    padding: 0;
    margin: 0;
}

ul {
    font-family: sans;
    list-style: none;
    padding: 0 0 0 1.5em;
}
ul ul {
	display: none;
}
span {
	cursor: pointer;
	font-weight: bold;
}

.expanded::before {
	content: "▼ ";
}

span::before {
	content: "▶ ";
}
</style>
<script type="text/javascript">
"use strict";
function toggleChildren(t) {
	var c = t.next