JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://canvasjs.com/assets/script/canvasjs.min.js"></script>
<br/><!-- Just so that JSFiddle's Result label doesn't overlap the Chart -->
<div id="chartContainer" style="height: 360px; width: 100%;"></div>

JavaScript

var chart = new CanvasJS.Chart("chartContainer",
{  
	backgroundColor: "#444",
  title: {
  	text: "My Chart",
    fontColor: "#fff"
  },
  axisX: {
  	stripLines: [
    	{
      	value: 20,
        label: "stripline"
      }
    ]
  },
  data: [
	{
		type: "line",
    showInLegend: true,
		dataPoints: [
			{ x: 10, y: 71 },
			{ x: 20, y: 55 },
			{ x: 30, y: 50 },
			{ x: 40, y: 65 },
			{ x: 50, y: 95 },
			{ x: 60, y: 68 },
			{ x: 70, y: 28 },
			{ x: 80, y: 34 },
			{ x: 90, y: 14 }
		]
	},
  {
		type: "line",
    showInLegend: true,
		dataPoints: [
			{ x: 10, y: 61 },
			{ x: 20, y: 45 },
			{ x: 30, y: 80 },
			{ x: 40, y: 35 },
			{ x: 50, y: 75 },
			{ x: 60, y: 64 },
			{ x: 70, y: 35 },
			{ x: 80, y: 68 },
			{ x: 90, y: 53 }
		]
	}		
	]
});

chart.render();
var max = chart.axisX[0].get("maximum");
var min = chart.axisX[0].get("minimum");
var stripLineOptions = {
	startValue: max,
  endValue: min,                
  color: "#fff",
};
chart.legend.set("fontColor", "#fff", false);
chart.axisX[0].set("labelFontColor", "#fff", false);
chart.axisY[0].set("labelFontColor", "#fff", false);
chart.axisX[0].set("stripLines", [stripLineOptions].concat(chart.axisX[0].stripLines));