random-quizlet.js

var last = $('.CardsList-progress span:last-child').text() * 1;
var getNext = function(){ return Math.floor(Math.random() * last) + 1; };
var current = $('.CardsList-progress span:first-child').text() * 1;
var next = getNext();
while (current == next) next = getNext();
console.log('current: ', current, ' next: ', next, ' of: ', last);
var times = Math.abs(current - next);
while (times--){
  $((current < next) ? '.nextButton' : '.previousButton').click();
}