The SVG eye mark
The first eye was a logo: two rings, an arc and a pupil that follows the cursor, redrawn once for each era. It set the idea that one thing can be seen through many screens.
Six of the ten marks, running as they did in May. Each keeps the same silhouette and changes only the way it is drawn.
What it was
Plain SVG and a spring. The pupil's position came from the cursor, and each era had its own small component that drew the same four shapes in its own manner: phosphor cells, a 1-bit bitmap, a hyperlink, candy gel, a flat icon.
The first-visit screen was a row of these. You scrolled along it and picked a year.
What it left behind
Two things carried into every later eye. The first is the idea itself: the era is a way of drawing, and the subject stays the same. The second is the input. Sweep to travel through time, tap the eye to enter. The loader still works that way.
Why it was not enough
A mark can look at you. It cannot be looked into. The picker needed something a visitor would stay with for a few seconds, and a logo is read in one.