<!DOCTYPE html>
<html>
<head>
<title>Recursive Traversal</title>
<style>
.comment {
margin: 10px;
padding: 10px;
border: 1px solid #ccc;
}
.reply {
margin-left: 20px;
border-left: 2px solid #aaa;
}
</style>
</head>
<body>
<div class="comments">
<div class="comment">
<p>Comment 1</p>
<div class="reply">
<p>Reply 1-1</p>
<div class="reply">
<p>Reply 1-1-1</p>
</div>
</div>
<div class="reply">
<p>Reply 1-2</p>
</div>
</div>
<div class="comment">
<p>Comment 2</p>
<div class="reply">
<p>Reply 2-1</p>
</div>
</div>