JSFiddle - React, Tailwind, and code Playground

JavaScript

<script type="text/javascript">
  var totalDistance = 0.0; 
  var lastLat; 
  var lastLong; 
 
  function toRadians(degree) { 
   return degree * Math.PI / 180; 
  } 
 
  function distance(latitude1, longitude1, latitude2, longitude2) { 
   // R is the radius of the earth in kilometers 
   var R = 6371;  
   var deltaLatitude = toRadians(latitude2-latitude1); 
   var deltaLongitude = toRadians(longitude2-longitude1); 
   latitude1 = toRadians(latitude1); 
   latitude2 = toRadians(latitude2); 
 
   var a = Math.sin(deltaLatitude/2) * 
    Math.sin(deltaLatitude/2) + 
    Math.cos(latitude1) * 
    Math.cos(latitude2) * 
    Math.sin(deltaLongitude/2) * 
    Math.sin(deltaLongitude/2); 
 
   var c = 2 * Math.atan2(Math.sqrt(a), 
   Math.sqrt(1-a)); 
   var d = R * c; 
   return d; 
  } 
 
 
  function updateStatus(message) { 
   document.getElementById("status").innerHTML = message; 
  } 
 
  function loadDemo() { 
   if(navigator.geolocation) { 
    updateStatus("HTML5 Geolocation is supported in your browser."); 
    navigator.geolocation.watchPosition(updateLocation, 
      handleLocationError, 
      {maximumAge:20000}); 
   } 
  } 
 
  window.addEventListener("load", loadDemo, true); 
 
  function updateLocation(position) { 
   var latitude = position.coords.latitude; 
   var longitude = position.coords.longitude; 
   var accuracy = position.coords.accuracy; 
   var timestamp = position.timestamp; 
 
   document.getElementById("latitude").innerHTML = latitude; 
   document.getElementById("longitude").innerHTML = longitude; 
   document.getElementById("accuracy").innerHTML = accuracy; 
   document.getElementById("timestamp").innerHTML = timestamp; 
 
   // sanity test... don't calculate distance if accuracy 
   // value too large 
   if (accuracy >= 500) { 
    updateStatus("Need more accurate values to calculate distance."); 
    return; 
   } 
   
   // calculate distance 
   if ((lastLat !== null) && (lastLong !== null)) { 
    var currentDistance =...