Hello,
I successfully customize my chapter title with those custom stylesheet :
xsl:attribute-set name=chap.title.properties
xsl:attribute name=color
xsl:value-of select=$title.color/
/xsl:attribute
xsl:attribute name=font-weightbold/xsl:attribute
Thanks Dave for the suggestion.
The fix that works for me is to add the following code inside the element:
l:i18n xmlns:l=http://docbook.sourceforge.net/xmlns/l10n/1.0; in the
file website-common.xsl:
l:l10n language=es
l:context name=title
l:template name=webpage text=%t/