fix: correct regression with code highlighting in dark mode

[robertwtucker]

Prerequisites

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• This pull request fixes a bug.
• This pull request adds a feature.
• This pull request introduces breaking change.

Description

This PR reverts a regression error in which the foreground color specified for highlighted code is almost indistinguishable from the white background used in dark mode.

This was originally fixed in 29a7a94 / #630 by assigning color: $fg-color from the light scheme variables (resolves to #212121). In 476429d, the assignment was changed to $fg-color-dark (resolves to #dadada) but this resulted in a color that is too close to the white of the code highlight to be read easily. See image:

This fix assigns $bg-color-dark which resolves to #212121 (same as the original fix). With this change applied, the code is now legible:

Issues Resolved

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Checklist

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General

• Describe what changes are being made
• Explain why and how the changes were necessary and implemented respectively
• Reference issue with #<ISSUE_NO> if applicable

Resources

• If you have changed any SCSS code, run make release to regenerate all CSS files

Contributors

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[luizdepra]

I will accept this, but I fear that using a different option of code highlight colors could result in the same problem. Let's see.