XML is concerned with content, and says nothing about how that content should be presented to the reader or rendered on paper. Multiple style sheet languages have been developed to describe visual layout, including Extensible Stylesheet Language Transformation (XSLT), Document Style Semantics and Specification Language (DSSSL), and Cascading Style Sheets (CSS).
The FDP documents use XSLT stylesheets to transform DocBook into XHTML, and then CSS formatting is applied to the XHTML pages. Printable output is currently rendered with legacy DSSSL stylesheets, but this will probably change in the future.
Cascading Style Sheets (CSS) are a mechanism for attaching style information (font, weight, size, color, and so forth) to elements in an XHTML document without abusing XHTML to do so.
The FreeBSD XSLT and
DSSSL stylesheets refer to
docbook.css, which is expected to be
present in the same directory as the XHTML
files. The project-wide CSS file is copied
from doc/share/misc/docbook.css when
documents are converted to XHTML, and is
installed automatically.
All FreeBSD documents are available for download at https://download.freebsd.org/ftp/doc/
Questions that are not answered by the
documentation may be
sent to <freebsd-questions@FreeBSD.org>.
Send questions about this document to <freebsd-doc@FreeBSD.org>.