{"id":177,"slug":"nng-mega-menu-hover-protocol-500ms","title":"NN/g mega-menu hover protocol: wait 0.5s before showing, then display within 0.1s","kind":"reference","scope":"business","status":"current","audiences":["claude-code","dev","candid-team"],"topics":["information-architecture","navigation-design"],"reference_body":"**Quote (Jakob Nielsen, NN/g):**\n\n> \"Wait 0.5 seconds. If the pointer is still hovering over a navbar item, display its mega menu within 0.1 seconds.\"\n\n**Source:** <https://www.nngroup.com/articles/mega-menus-work-well/>\n\n**Confidence:** Verified.\n\n**Why this matters:** Mega menus that fire instantly on hover flicker open as the cursor passes over the nav. The 500ms delay prevents flicker; the 100ms reveal is fast enough to feel responsive. **Implementation note for Candid sites:** use `setTimeout(show, 500)` with cancellation on `mouseleave`. Touch users get an immediate response on tap (no hover state). See [[rule-implement-megamenu-with-hover-delay]].","rationale_body":null,"metadata":null,"links":{"outgoing":[{"slug":"nielsen-mega-menus-show-everything-at-glance","title":"Jakob Nielsen: \"Mega menus show everything at a glance, so users can see rather than try to remember\"","kind":"reference","scope":"business","link_type":"depends-on"}],"incoming":[{"slug":"rule-expose-industry-and-service-as-orthogonal-axes","title":"RULE: Expose Industries and Services as two orthogonal axes in the top nav. Don't hide one behind the other.","kind":"rule","scope":"business","link_type":"depends-on"},{"slug":"rule-implement-megamenu-with-hover-delay","title":"RULE: Mega menu hover delay 500ms before show, 100ms reveal. Mobile uses accordion / sequential, not the same mega menu.","kind":"rule","scope":"business","link_type":"depends-on"},{"slug":"research-brief-ia-multi-vertical-service-business","title":"Research brief: Information architecture for service businesses with multiple verticals (piece 6 of 15)","kind":"reference","scope":"business","link_type":"relates-to"}]},"created_at":"2026-05-22T19:40:49.007Z","updated_at":"2026-05-22T19:40:49.007Z"}