lfs-book/stylesheets/lfs-xsl/docbook-xsl-1.78.1/params/user.css.xml

<refentry xmlns="http://docbook.org/ns/docbook"
          xmlns:xlink="http://www.w3.org/1999/xlink"
          xmlns:xi="http://www.w3.org/2001/XInclude"
          xmlns:src="http://nwalsh.com/xmlns/litprog/fragment"
          xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
          version="5.0" xml:id="user.css">
<refmeta>
<refentrytitle>user.css</refentrytitle>
<refmiscinfo class="other" otherclass="datatype">filename</refmiscinfo>
</refmeta>
<refnamediv>
<refname>user.css</refname>
<refpurpose>Specifies the path to user-supplied CSS</refpurpose>
</refnamediv>

<refsynopsisdiv>
  <src:fragment xml:id="user.css.frag">
    <xsl:param name="user.css">user.css</xsl:param>
  </src:fragment>
</refsynopsisdiv>

<refsection><info><title>Description</title></info>

<para>This parameter specifies the path from where the
  CSS styling is read.  This file can be used to
  add additional styling to the slides.</para>

</refsection>
</refentry>