| Key | Action |
|---|---|
| Tab | Move focus into / out of the tree |
| ↓ / ↑ | Move to next / previous visible node |
| → | Expand collapsed node, or move to first child |
| ← | Collapse expanded node, or move to parent |
| Home | Move to root node |
| End | Move to last visible node |
| Enter | Expand / collapse node |
| Space | Toggle selection on focused node |
| a–z | Type-ahead: jump to next node whose name starts with the character |
All nodes carry role="treeitem" with aria-level, aria-posinset,
aria-setsize, aria-expanded, and a descriptive aria-label. The root SVG has
role="tree" and aria-label="Organizational chart" (configurable via
a11y.label).