[wonger_]

(not author) from the source:

  const { latitude = "0", longitude = "0" } = Astro.locals.runtime.cf || {};

To do it client-side, you would probably have to call some less-reputable IP geolocation service, or settle for navigator.geolocation which has a permission popup

[mcteamster]

Depending on how "approximate" is acceptable, I've found that using timezone names can be a good proxy for location. As most users have their timezones set correctly it's more consistent and private than IP or GPS.

I've made a library for my own use cases that does this (https://github.com/mcteamster/virgo), but it's also pretty straightforward to parse the city/state name out of the timezone and look it up somewhere.