Four anchors registered as moderate-eagerness prefetch candidates via the
<script type="speculationrules"> document rule above.
Scroll until the gradient HERO card visually fills the viewport, stop and
wait ~600ms; the heuristic picks the anchor with the largest
size_in_viewport. Move the mouse off the page first to remove
hover-triggered prefetches from the trigger column.
This card is min-height: 70vh. When it visually fills the
viewport it dominates by size_in_viewport. The heuristic
picks this and prefetches target.html.