Fuse — free browser game

You're the technician at a substation: the control board in front of you has four circuits numbered 1 through 4, each shown as a vertical bar filling from bottom to top with its current load. Your job is to keep every bar from reaching the top for as long as possible. Each circuit has its own random baseline load rate, all of which climb together as the round progresses, and on top of that a circuit will occasionally take a 'surge' — a sudden load spike. To vent a circuit, press 1, 2, 3 or 4 on the keyboard (or tap its bar/button on touch); that circuit's load drops by 40 points instantly. The catch: half of the vented current is pushed to the left neighbor and half to the right neighbor (on edge circuits, the full amount goes to the only adjacent one), so blindly venting the highest bar often blows up its neighbor. Each circuit has a 1.4-second cooldown bar underneath; until it refills you can't vent that circuit again, so spamming one circuit isn't a strategy. The moment any circuit's load passes 100%, the fuse blows and the round ends; the seconds you survived become your score and your best time is saved locally. Strategy: before venting a hot bar, check which neighbor is safe — bleed going into an already-full neighbor blows the chain; vent that neighbor first, then hit the target. For the middle circuits (2 and 3) with two low neighbors the bleed is almost free; the edge circuits (1 and 4) dump the whole bleed onto a single neighbor, so catch them early. Track your cooldowns in your head — by the moment you need all four keys at once, the round is already over.