很好用的 CSS 目录树

<div id="sidebar">
<ul>
	<li>
<h2>Low-Limited Texas Holdem</h2>
<ul>
	<li><a href="/advice/">General Advice</a></li>
	<li><a href="/position/">Position</a></li>
	<li><a href="/hands/">Reading your hands</a></li>
	<li><a href="/bluffing/">Bluffing</a></li>
</ul>
</li>
	<li>
<h2>Texas Holdem Tournament</h2>
<ul>
	<li><a href="/rules-rewards/">Rules and rewards distribution</a></li>
	<li><a href="/tournaments/">From Nobody to Somebody</a></li>
	<li><a href="/no-limit-tournament/">No-limit Tournament Advice</a></li>
</ul>
</li>
	<li>
<h2>Online Texas Holdem Strategy</h2>
<ul>
	<li><a href="/online/">Online vs. Offline</a></li>
	<li><a href="/tips-strategy/">Tips and Strategy</a></li>
</ul>
</li>
</ul>
</div>

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#sidebar ul {margin:0;list-style:none; padding:0;}
#sidebar ul li {margin:0; padding:0 0 10px 0; display:block;}
#sidebar ul ul {margin: 0; list-style:none; padding:0;}
#sidebar ul ul li {padding:0; height:25px; margin:0; background:url(images/libg.gif) no-repeat;}
#sidebar a{text-decoration:none;color:#0f0; display:block; padding:0px 10px 0px 15px; line-height:25px; font-size: 12px; }
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