JSFiddle - React, Tailwind, and code Playground

HTML

<script src="http://code.highcharts.com/highcharts.js"></script>
<script src="http://code.highcharts.com/modules/exporting.js"></script>

<div id="chart" style="min-width: 310px; height: 400px; margin: 0 auto"></div>

JavaScript

$(function () {
    
    var d1 = [
          [Date.UTC(2014,0,16), 173.33],
          [Date.UTC(2014,0,23), 163.33],
          [Date.UTC(2014,0,30), 137.67],
          [Date.UTC(2014,1,6), 176.33],
          [Date.UTC(2014,1,13), 178.67],
          [Date.UTC(2014,1,27), 167.33],
        ];
        
    var d2 =  [
          [Date.UTC(2014,0,11), 156.33],
          [Date.UTC(2014,1,15), 167.67],
        ];
    
    var d3 = [
          [Date.UTC(2014,0,1), 135],
          [Date.UTC(2014,0,5), 146.33],
          [Date.UTC(2014,0,27), 146.75],
        ];
        
   xs = []; ys = [];
    var minX = 1E100;
    var maxX = -1E100;
    $.each([d1,d2,d3], function(i,j){
        $.each(j, function(i,k){
            if (k[0] < minX) minX = k[0];
            if (k[0] > maxX) maxX = k[0];
            xs.push(k[0]);
            ys.push(k[1]);
        });
    });
    
    reg = {}
    lineFit(xs,ys,reg);
        
   $('#chart').highcharts({
      chart: { type: 'spline' },
      title: { text: '' },
      xAxis: { type: 'datetime' },
      yAxis: {
        title: { text: '' }
      },
      series: [{
        name: 'Line 1',
        data: d1,
        color: 'purple'
      },
      {
        name: 'Line 2',
        data: d2,
        color: 'green'
      },
      {
        name: 'Line 3',
        data: d3,
        color: 'blue'
      },
      {
        name: 'Regression Line',
        data: [[minX, reg.slope * minX + reg.intercept], 
               [maxX, reg.slope * maxX + reg.intercept]],
        color: 'red',
        marker:{enabled:false},
        lineWidth: 5
      }]
    });    
});

    //utility functions
    lineFit = function(xs, ys, rV){
        rV.slope = 0.0;
        rV.intercept = 0.0;
        rV.rSquared = 1.0; // assume perfection
        
        if (xs.length < 2)
        {
            return false;
        }
        
        if (xs.Count != ys.Count)
        {
            return false;
        }
        
        var N = xs.length;
        var sumX =...