Links in the site's left sidebar don't have a hover effect

[dario-piotrowicz]

In the /learn and /about routes the links present in the sidebar on the left don't have a hover state but I think they should (in the same way the left sidebar on https://nodejs.org/docs/latest/api/ does it)

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Original context for the issue: nodejs/api-docs-tooling#285 (comment)

[AugustinMauroy]

it's should be same hover effect Than languagedropdown on header