[Techstack-beta] Site-wide: console and code blocks styles inconsistent

[samueldr]

Both inconsistent within the new site, and inconsistent with the previous implementation.

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Here's a screenshot from the Download page, where the new implementation is proper for a commands block:

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Here's, comparatively, a screenshot from the How Nix Works page, showing an off-model commands block:

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You may have noticed I'm using commands block here. This is because a stylistic decision was made to have code blocks on light, and terminal sessions on dark.

Source code blocks are always off-model in the new implementation.

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Side-note: the only story in the stories section is off-model in the old site.

[thilobillerbeck]

Will he part of a fix shortly