Served by the Worker in dev. The launcher belongs bottom right; open it and ask something. GTM-236's acceptance is this page in a real browser, not a test: the launcher renders, the panel opens, a message round-trips, and a reload resumes the conversation.
This page's own CSS is deliberately ugly and unscoped. The widget must ignore all of it, because the real host
page is gtmify.io and its stylesheet is far larger than this one.
A round-trip needs OPENROUTER_API_KEY in a gitignored .dev.vars. Without it the panel
still opens and the send path still runs; the reply comes back as the trouble message instead.