## ADDED Requirements

### Requirement: Direct Track Background Image Rendering

The system SHALL render Direct Track PDF output using a full-page background image with an invisible text overlay to preserve visual fidelity while maintaining text extractability.

#### Scenario: Render Direct Track PDF with background image
- **WHEN** generating Layout PDF for a Direct Track document
- **THEN** the system SHALL render each source PDF page as a full-page background image at 2x resolution
- **AND** overlay invisible text elements using PDF Text Rendering Mode 3
- **AND** the invisible text SHALL be positioned at original coordinates for accurate selection

#### Scenario: Handle Office documents (PPT, DOC, XLS)
- **WHEN** processing an Office document converted to PDF
- **THEN** the system SHALL use the same background image + invisible text approach
- **AND** preserve all visual elements including vector graphics, gradients, and complex layouts
- **AND** the converted PDF in result directory SHALL be used as background source

#### Scenario: Handle native editable PDFs
- **WHEN** processing a native PDF through Direct Track
- **THEN** the system SHALL use the source PDF for background rendering
- **AND** apply the same invisible text overlay approach
- **AND** chart regions SHALL be excluded from the text layer

### Requirement: Chart Region Text Exclusion

The system SHALL exclude text elements within chart regions from the invisible text layer to prevent duplicate content and unnecessary translation.

#### Scenario: Detect chart regions
- **WHEN** classifying page elements for Direct Track
- **THEN** the system SHALL identify elements with type CHART
- **AND** add chart bounding boxes to regions_to_avoid list

#### Scenario: Exclude chart-internal text from invisible layer
- **WHEN** rendering invisible text layer
- **THEN** the system SHALL skip text elements whose bounding boxes overlap with chart regions
- **AND** chart axis labels, legends, and data labels SHALL NOT be in the invisible text layer
- **AND** these texts remain visible in the background image

#### Scenario: Chart text not available for translation
- **WHEN** extracting text for translation from a Direct Track document
- **THEN** chart-internal text SHALL NOT be included in translatable elements
- **AND** this is expected behavior as chart labels typically don't require translation