Not sure how I didn't catch this -- probably because I spent a long time getting it right in inverted and DarkReader modes, and accidentally overrode the standard dark mode style -- but in the original dark mode, still recommended for Wikimedia ZIMs, the close icon is faded and rather difficult to see (screenshot). Should be an easy fix in the dark mode stylesheet.
Not sure how I didn't catch this -- probably because I spent a long time getting it right in inverted and DarkReader modes, and accidentally overrode the standard dark mode style -- but in the original dark mode, still recommended for Wikimedia ZIMs, the close icon is faded and rather difficult to see (screenshot). Should be an easy fix in the dark mode stylesheet.