Render dividers (rules between rows/sections) and spacers (fixed gaps between elements) as their own standalone elements, with the surrounding gap owned by the layout — never as a `border-t`/`border-b` plus `py-*`, or an `mt-*`/`mb-*`, glued onto a content element. Use when adding a divider between list rows or panel sections, inserting fixed space between elements, reviewing layout code that fakes spacing with padding/margin on bordered blocks, or when you catch yourself debating whether a margin belongs to the element above or below.
