## ADDED Requirements

### Requirement: Reserved bottom chrome on video study stage
On iPad and PC video study surfaces, the system SHALL reserve fixed bottom regions for a waveform strip and an AI toolbar so that the video stage height excludes those regions. Native browser media controls MUST NOT occupy the reserved chrome.

#### Scenario: Video stage leaves room for chrome
- **WHEN** a learner opens a video (or video+PDF) study session on iPad or PC
- **THEN** the playable video area sits above a waveform strip and an AI toolbar whose combined height remains available and is not covered by the video frame

### Requirement: Waveform strip playback chrome
The waveform strip SHALL show media progress with an amplitude visualization and minimal transport controls (play/pause and time). Seeking via the strip MUST update media currentTime.

#### Scenario: Seek on waveform
- **WHEN** the learner taps or drags on the waveform strip
- **THEN** playback position moves to the corresponding time and the time label updates

### Requirement: AI toolbar replaces floating AI FAB
The study UI SHALL expose AI actions on the bottom toolbar (previous-sentence / audio clip, voice call, video preview, annotate/pencil, message) and MUST NOT rely on a floating AI FAB as the primary entry on video stages when this chrome is enabled.

#### Scenario: Primary AI entry is toolbar
- **WHEN** video study chrome is enabled and AI config is available
- **THEN** the learner can reach ask / call / annotate actions from the bottom toolbar without opening a floating AI FAB

### Requirement: Minimal SVG toolbar icons
Toolbar action icons for phone, video, pencil, message (and related TTS/mic affordances) MUST use stroke SVG icons consistent with the app icon set (`Icons.tsx` style). Emoji MUST NOT be used as primary toolbar glyphs.

#### Scenario: Voice and video use SVG icons
- **WHEN** the AI toolbar is rendered
- **THEN** voice-call and video controls display SVG icons (not emoji) that follow the app’s minimal outline style

### Requirement: Toolbar opens ask modal by media kind
Activating audio/previous-sentence, video, screenshot/pencil-confirm, or message controls SHALL open the Ask modal with the matching left-pane preview kind (audio clip, video, image, or paused frame). Bottom chips/tags for buffer or clip SHALL also open the corresponding preview.

#### Scenario: Message icon opens dialog with frame
- **WHEN** the learner taps the message icon
- **THEN** playback pauses, a full-frame capture is prepared, and the Ask modal opens with image preview and conversation pane

#### Scenario: Video icon opens video preview dialog
- **WHEN** the learner taps the video toolbar icon
- **THEN** the Ask modal opens with a video preview pane (screen-share call entry lives in the modal chrome, not as an immediate full-screen call)

### Requirement: Feature and config gating on toolbar actions
Toolbar actions MUST be hidden or disabled when the corresponding `AiFeatures` flag is off or when no usable endpoint for that action can be resolved. Unavailable actions MUST show clear disabled or messaging state rather than sending requests.

#### Scenario: Voice call disabled by feature flag
- **WHEN** `features.realtimeVoiceCall` is false
- **THEN** the phone/voice-call control is hidden or disabled and does not start a call session