Description

Fix the --roundness CSS variable override in the Dark Note theme, which incorrectly targets the account menu's first child.

Current look on hover:

The fix adds precision to the selector to avoid targetting .buttons that are children of .accountButtonAndMenu, fixing that very issue.
There might be other places this variable incorrectly impacts, but I don't know the codebase so any insight is welcome. If there's none but still a better/different selector to use, let me know too!

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