JSFiddle - React, Tailwind, and code Playground

JavaScript

var SeriesList = [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26];

var firstHalf = SeriesList.slice(0,12);
var secondHalf = SeriesList.slice(13,26);
console.log(firstHalf, secondHalf);

// shuffle the series list to a random order
    for(var i=SeriesList.length-13; i>0; i--) 
    {
        var j = Math.floor(Math.random() * (i+1));
        var x = SeriesList[i];
        SeriesList[i] = SeriesList[j];
        SeriesList[j] = x;
    }
        for(var i={from: 12, to: 23}; i>0; i--) 
    {
        var j = Math.floor(Math.random() * (i+1));
        var x = SeriesList[i];
        SeriesList[i] = SeriesList[j];
        SeriesList[j] = x;
    }