toc.line.properties — Properties for lines in ToC and LoTs
<xsl:attribute-set name="toc.line.properties">
<xsl:attribute name="text-align-last">justify</xsl:attribute>
<xsl:attribute name="text-align">start</xsl:attribute>
<xsl:attribute name="end-indent"><xsl:value-of select="concat($toc.indent.width, 'pt')"></xsl:value-of></xsl:attribute>
<xsl:attribute name="last-line-end-indent"><xsl:value-of select="concat('-', $toc.indent.width, 'pt')"></xsl:value-of></xsl:attribute>
</xsl:attribute-set>
Properties which are applied to every line in ToC (or LoT). You can modify them in order to change appearance of all, or some lines. For example in order to make lines for chapters in bold specify the following in your customization layer.
<xsl:attribute-set name="toc.line.properties">
<xsl:attribute name="font-weight">
<xsl:when test="self::chapter | self::preface | self::appendix">bold</xsl:when>
<xsl:otherwise>normal</xsl:otherwise>
</xsl:attribute>
</xsl:attribute-set>