## ADDED Requirements

### Requirement: Theme choice persists across sessions
The system SHALL persist user-selected theme with localStorage as primary storage and cookie fallback when localStorage is unavailable.

#### Scenario: Persist theme in localStorage
- **WHEN** localStorage is available and user selects a theme
- **THEN** selected theme is saved in localStorage
- **AND** stored value is used on next visit in same browser

#### Scenario: Cookie fallback persistence
- **WHEN** localStorage is unavailable or blocked
- **THEN** selected theme is saved in cookie storage
- **AND** cookie value is used to restore theme on return visit