What readers see

Strata stay out of the way until a reader wants them.

Marked shapes

A shape carrying a stratum is marked on the canvas. The mark is the only change to the drawing, and a reader who never clicks one still sees the complete diagram.

Hover

Hovering a marked shape for half a second shows a preview card with the stratum's name and its opening lines. Enough to decide whether to click.

The window

Clicking opens the stratum in a floating window. Readers can move it, resize it from any corner, maximise it, or minimise it to a strip.

The dock

The window can be docked to a panel down the right-hand side, half the viewport wide by default and draggable from there. The page reflows around it rather than being covered.

Dock the panel to work through a diagram shape by shape while the drawing stays put.