Improve scroll to top behaviour

Hardcoded values are now replaced by calculated ones. The current position is now calculated and passed on correctly, so that the current scroll position is always held until the sticky position. As soon as the scroll position is below the sticky position, the menu remains sticky and the content is set to the beginning.

mentioned in merge request !10 (merged)

Can you describe what this changes or what cases this improves?

changed the description

merged

mentioned in commit 1972b2ce

Thanks!