Facets (or "Filters") are used on pages with lots of content such as search results, people, and news stories.
On desktop, facet options display in the left sidebar with a search box generally included at the top. Checkboxes are used to turn on or off facets. Additional items can be nested within the relevant category.
On phone, facets drop down from immediately under the primary color field.
On both desktop and phone, active facets display at the top of the page (and can be deleted there individually) and, on desktop, a "Clear Selections" button appears at the top of the left sidebar after one facet has been selected.
We can accommodate pretty much any type of facet grouping requested.