pass a parameter from the URL using Javascript

I declare my parameter at the top of the xsl stylesheet, like that:
<xsl:param name="page_number" select=" 1 "/>
iI change the select value and i get the h2 that i want.

	<div class="section">
			<h2>Chris</h2>
			<p>text</p>
			<p>text</p>
		</div>
		<div class="section">
			<h2>
				<a href="http://www.mypage.com">Leo</a>
			</h2>
		</div>
		<div class="section">
			<h2>George</h2>
			<p>text</p>
		</div>
		<div class="section">
			<h2>Alex</h2>
			<p>text</p>
			<p>text</p>
		</div>

<xsl:when test="//xhtml:div[@class='section'][position()=$page_number]">
</xsl:template>