State Machine Clock

A clock is three nested finite state machines: a mod-60 seconds counter feeding a mod-60 minutes counter, feeding a mod-24 hours counter — each ring only advances when the ring inside it carries.
00:00:00
H = 00 (mod 24, increments on minutes carry) ⚡ CARRY
M = 00 (mod 60, increments on seconds carry) ⚡ CARRY
S = 00 (mod 60, increments every tick)
Outer ring: hours · middle ring: minutes · inner ring: seconds. The glowing arc is the most recent transition; the line between rings is a carry.
Installable — works offline once loaded once.