## ADDED Requirements

### Requirement: Mobile Bottom Navigation
The system SHALL display a bottom tab bar for navigation on mobile viewports (width < 768px).

#### Scenario: Mobile viewport shows bottom nav
- **WHEN** the app is viewed on a device with width less than 768px
- **THEN** a bottom tab bar is displayed at the bottom of the screen
- **AND** it contains tabs for: Home, Projects, Sessions, Tools, Settings
- **AND** the desktop sidebar navigation is hidden

#### Scenario: Bottom nav tab selection
- **WHEN** user taps a tab in the bottom navigation
- **THEN** the app navigates to the corresponding route
- **AND** the selected tab shows an active state

#### Scenario: Bottom nav session badge
- **GIVEN** the user has active sessions
- **WHEN** viewing the bottom navigation
- **THEN** the Sessions tab displays a badge with the active session count

#### Scenario: Desktop viewport shows sidebar
- **WHEN** the app is viewed on a device with width 768px or greater
- **THEN** the desktop sidebar navigation is displayed
- **AND** the bottom tab bar is hidden

### Requirement: Safe Area Support
The system SHALL account for mobile safe areas (notch, home indicator) in the bottom navigation.

#### Scenario: iPhone with home indicator
- **GIVEN** an iPhone with a home indicator
- **WHEN** the bottom navigation is displayed
- **THEN** it includes additional padding to avoid the home indicator
- **AND** all navigation tabs remain fully tappable
