You are cracking a five-letter combination lock, one pin at a time, left to right.
Scroll (mouse wheel, trackpad, or swipe up/down on mobile) to spin through letters on the active pin.
Tap UNLOCK to test your pick. If correct, the pin locks and you move to the next one. If wrong, you lose time.
The pin glows to hint how close you are. Blue means cold, amber means warm, red means hot. Later pins give fewer hints, and the last two give none at all.
Crack all five pins before the timer runs out. Good luck.