Photo — Stack top bottom
Prints appear one below another down the page, filling a ladder of fixed rungs, then drain from the bottom back up before refilling.
The page fills like a checklist: the first photograph sits at the top margin, the next appears a step below, and so on to the bottom, each print centred on its own rung. When the sequence reverses, the most recent prints vanish first, emptying the page from the bottom up.
The rungs are computed once — the height inside the margins divided by the size of the set — and the only animation is how many of them may show, a triangle wave over the loop. Nothing slides or fades; each photo either exists or doesn't, which gives the strip its stepped, metronomic cadence.
