Pelican provides support for generating content from two markup languages - reStructuredText (the default) and Markdown (if installed). For the most part both markup languages generate similar output, except when using Pygments to generate code blocks with syntax highlighting.
Code blocks generated from reStructuredText will use the CSS class
to handle the syntax highlighting, while Markdown will use the
class by default. This can cause problems when developing themes for Pelican
users who may be using either reStructuredText or Markdown, or users who choose
to generate content using both markup languages.
Fortunately you can customise how the Markdown processor generates its output
MD_EXTENSIONS setting in the
pelicanconf.py file. You can
configure the Markdown processor to generate code blocks using the
CSS class by inserting the following entry in you
MD_EXTENSIONS = ['codehilite(css_class=highlight)']
More information about pelicanconf.py settings can be found in the Pelican documentation.