Collapsible Filter Panel

For a filter set worth hiding by default — an uppercase title on the left, a chevron on the right that rotates when open. Use FilterBar instead when the filters should always be visible.

Props

Implementation notes

• Collapsing the panel must not clear its state. This component only controls visibility (via Radix Collapsible) — the filter values themselves live in whatever state the consumer already holds. Closing the panel to glance at results and reopening it should show the same selections, not a reset form.

Do / Don't

• Do default to closed (defaultOpen={false}, the default) for a filter set most visits don't need to touch — that's the whole point of making it collapsible.
• Don't put the search/apply button itself inside a way that only exists while expanded if the results below are meant to update live as filters change — collapsing to check a result shouldn't strand an unapplied change.