WenWare

Build a browser guessing game inspired by "WenWare": a time-travel GeoGuessr where players explore a 360° historical scene, then guess both WHERE (pin on a world map) and WHEN (a year slider) the moment took place.
Tech: Three.js (or a panorama viewer) for the 360° scene, plus a 2D map such as Leaflet. Single page, works on phone and desktop.
Core loop: show a panorama, let the player look around, then place a map pin and choose a year. Score each round by distance and by years off, show the true answer, play 5 rounds per game.
Content: start with a small JSON set of panoramas you have the rights to use, each with lat/lng, year and a one-line caption. Group them by era (Ancient, Medieval, Modern).
Extras the original has that you can add later: a daily 5-round challenge, a high-score table, and a 1v1 or party multiplayer mode.
Steps: 1) panorama viewer, 2) map pin + year slider + scoring, 3) results screen and 5-round game, 4) daily mode and high scores, 5) your own twist.
Make it your own: don't copy the original's name, art, text or code.