# Responsive and Print Behavior

## Desktop projection

- Canvas is 16:9 and centered within the viewport.
- Navigation stays outside the canvas.
- Essential text should normally be at least 18 px at a 1440×900 viewport; footnotes may be smaller if legible.
- No horizontal or vertical scrolling inside an active slide.

## Mobile review

- Switch the active slide from absolute 16:9 positioning to a vertical, scrollable reading surface.
- Move dense multi-column layouts to one column.
- Hide fullscreen controls that are not useful on a phone.
- Keep the bottom navigation from covering the last content block; reserve bottom padding.
- The assistant becomes a full-width drawer.

## Fullscreen

Use the original deck DOM with `requestFullscreen()`; do not clone the deck. Cloning duplicates IDs and disconnects event listeners. Test navigation, escape, and assistant open/close after entering fullscreen.

## Print/PDF

- Declare `@page { size: 16in 9in; margin: 0; }`.
- Force every slide, including normally hidden slides, to `display:flex` in print.
- Use `break-after: page`.
- Hide navigation, assistant, toasts, and interactive-only controls.
- Generate PDF with CSS page size enabled.
- Verify PDF page count equals manifest page count.

Screen and print are separate modes. A page that passes viewport overflow checks can still clip in PDF, so inspect both.
