Tap the menu, then tap a section.

Each level pushes the one before it off to the left. The back row walks it home.

What it does

Push navigation
Levels slide rather than expand in place, so a deep menu never becomes a long scroll.
Two-stage burger
The bars translate together, then rotate into the cross. Reversed on close.
Even distribution
Items divide the available height, so every level looks composed whatever it contains.
Arbitrary depth
Store goes three levels deep. Adding a fourth is markup only.
Keyboard and motion
Escape steps up a level then closes. Reduced-motion collapses the animation.