Almost every sports feed stores kick-off in UTC. Fans do not watch UTC. A 19:00 start printed as 16:00 is a number you have to translate every time you open the page. Live Score keeps the timestamp in UTC, then asks the browser which timezone it is in — Europe/Istanbul, Europe/Berlin, America/New_York — and prints HH:mm on that clock.
No GPS prompt. The timezone is the one already set on the device: Windows, phone, or laptop. If you travel and change the system timezone, the board follows on the next refresh.
Live minutes are a different kind of clock. They are not a timezone. They are the elapsed match time: 12', 45+', 78'. We print them next to the score.
When a fixture is still NS you see your local kick-off. In 1H or 2H you see the minute. Full time shows FT. The label under Today's Matches names the timezone in use so you can check it at a glance.