for (let i = len - 1; i = 0; i--) {
What that means is that my strategy for animating the button presses can be pretty straightforward, and will hinge on a function that flips the pressed-ness of whatever button corresponds to its argument. The overall logic will goes like this:
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В России предупредили о скорой нехватке вагонов08:46
Europe has the same tools. It simply uses them less decisively