monthlytracker/openspec/changes/archive/2026-03-23-theming-dark-mode/specs/dark-mode/spec.md

ADDED Requirements

Requirement: User can switch between light and dark themes

The system SHALL allow the user to toggle between light and dark themes with a persistent preference.

Scenario: User toggles dark mode on

• WHEN the user activates the theme toggle while the app is in light mode
• THEN the system applies the dark theme and saves the preference for future visits

Scenario: User toggles dark mode off

• WHEN the user activates the theme toggle while the app is in dark mode
• THEN the system applies the light theme and saves the preference for future visits

Requirement: Theme preference respects system defaults on first visit

The system SHALL use the user's system color scheme preference when no saved preference exists.

Scenario: No stored preference uses system theme

• WHEN the user opens the app for the first time without a saved theme preference
• THEN the system applies dark mode when the operating system prefers dark color schemes and light mode otherwise

Requirement: Theme selection loads without a flash of the wrong theme

The system SHALL initialize the theme before the first visible paint so the page does not briefly render in the wrong theme.

Scenario: Initial paint matches saved theme

• WHEN the app loads and a saved theme preference exists
• THEN the document theme is applied before the page content is visibly rendered