Improve analytics dashboards in dark mode
Issue
As noted in MR review comment, updates to the dashboard styles have not automatically worked with dark mode, and it has some differences, e.g.:
Panels, background
In light themes, the panel backgorund matches the page background. When editing the page background turns gray.
In dark mode, the panel backgrounds are different from the background, and there is no change when editing.
Chart labels
Chart labels render with a text colour the same as the panel background, so they are invisible:
(note missing Counts, Aug, Time labels from the chart)
Proposal
Write some custom CSS to override these styles in dark mode.