Sticky Scroll

Stick one column in place while the opposite column scrolls past it.

Trigger:
Scroll position within a two-column section.

Start:
The sticky column reaches the top of the viewport.

End:
The scrolling column finishes its content; the sticky column unpins as the section ends.

Behavior:
One column sticks in place for the duration of the section while the opposite column's content scrolls past it, keeping the two visually paired.

Initial state:
Sticky column: static, top: 0
Scrolling column: content starts at top

Final state:
Sticky column: still in place
Scrolling column: content fully scrolled past