# Accessibility

Office Tools uses semantic controls, visible focus, keyboard-operable file
selection and the shared Toolbox light/dark/system preference. The main content
width is `min(100%, 90rem)` and layouts collapse without horizontal page
overflow on narrow screens.

Viewer adapters should preserve meaningful headings, paragraphs, lists and table
semantics where the source exposes them. Spreadsheet grids need labelled row and
column headers plus a non-visual cell description. Presentation navigation needs
an announced slide position and a linear text alternative for each slide.

Colour alone must not communicate selection, errors or diagnostics. Animations
respect `prefers-reduced-motion`. Imported images use source alternative text
when available and an explicit fallback when it is absent.