You use the prismjs library for your fenced code block formatting and syntax highlighting. However, you've implemented ONLY the "Default" CSS from the prismjs library, which means the same exact colors are used for both light mode and dark mode pages. This requires us to manually create a set of CSS overrides for use in .dark_theme pages. (Otherwise, the code syntax highlighting and presentation is too dim/dark.)

The prismjs library already comes with many CSS variations. One of them called "Tomorrow Night" is ideal for your dark mode pages. If you implemented your fenced code block rendering to use "Tomorrow Night" by default for pages in dark mode, you would save us all a lot of headache fine-tuning presentation of code blocks in dark mode.