Depth used to cost width. Every expansion added a column to the right, so following a lineage meant scrolling sideways through a widget while the page sat still, and only a few levels were ever visible at once.
## Levels run down the page
Each level is now a horizontal band whose bar widths follow assembly counts, with the caption directly beneath its bar, and ribbons connect one captioned block to the next. Eukaryotes down to humans is about thirty levels and reads as one ordinary page scroll. The chart itself only scrolls sideways on screens too narrow to keep labels legible.
Two things that only showed up once it was rendered:
* Captions have to sit below their bar, with the ribbons leaving from the bottom of the whole block. Running ribbons bar-to-bar drew every flow straight through the labels of the level it was leaving.
* Expanding now nudges the page down only when the new level has fallen past the viewport, instead of scrolling the widget to its right edge.
## Shortcuts
…
Add clade silhouettes, compact navigation tabs, and drop the hover underline (#3)
