Thin upgrade over the native Popover API. The popover lives in the top layer with light-dismiss and Escape handled by the browser, and a button with popovertarget (or command="toggle-popover") opens it with no JavaScript. CSS anchor positioning places it against the invoker. This enhancer only mirrors aria-expanded onto the invokers, runs a JS positioning fallback on engines without anchor positioning, adds optional hover triggering, and exposes an imperative open/close API.