Mobile header strip carries the current section title in its centre
slot ("Dashboard" / "Reminders" / etc.). The top-level pages were
ALSO rendering the same string in an H1 right below — duplicate
labelling, wasted vertical space, and the H1 was the first thing
that overlapped the header on tight viewports.
Switched the four duplicates to `hidden sm:block`:
- / (Dashboard)
- /reminders
- /activity
- /settings
Desktop sidebar has no per-page title chip, so the H1 stays visible
sm: and up. Sub-pages (account detail, group detail, reminder
detail, "New Reminder", "Add Account") have dynamic H1s that don't
duplicate the header — those keep their visibility unchanged.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>