fix: don't leave toc mode in nested TOCs

src/main/webapp/stylesheets/tohtml.xsl

@@ -107,7 +107,7 @@
                     </a>
                     <xsl:if test="$currentDepth &lt; $tocDepth and (descendant::div[head] or descendant::TEI)">
                             <ul>
-                                    <xsl:apply-templates>
+                                    <xsl:apply-templates mode="#current">
                                             <xsl:with-param name="currentDepth" tunnel="yes" select="$currentDepth + 1"/>
                                     </xsl:apply-templates>
                             </ul>