25C PDF generation from example template issues

Summary:

Started exploring the PDF feature added in 25C and immediately hit an issue when using the example HTML template supplied in the documentation. Saving the example into a *.html file allows it to load correctly in the browser:

However, when the 'Generate PDF for Printing and Sharing' option is selected on the form, this is the output:

The structure of the HTML is intact, but the coloured styling is missing.

Has anyone else faced this?

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