JSFiddle - React, Tailwind, and code Playground

HTML

<link rel="stylesheet" href="https://unpkg.com/[email protected]/dist/leaflet.css" integrity="sha512-Rksm5RenBEKSKFjgI3a41vrjkw4EVPlJ3+OiI65vTjIdo9brlAacEuKOiQ5OFh7cOI1bkDwLqdLw3Zg0cRJAAQ==" crossorigin="" />
<script src="https://unpkg.com/[email protected]/dist/leaflet.js" integrity="sha512-/Nsx9X4HebavoBvEBuyp3I7od5tA0UzAxs+j83KgC8PU0kgB4XiK4Lfe4y4cgBtaRJQEIFCW+oC506aPT2L1zw==" crossorigin=""></script>

<div id="map" tabindex="0" data-lat="51.67204" data-lon="39.1843" data-size="12"></div>
<div class="sss">
   0
</div>

CSS

body {
  padding: 0;
  margin: 0;
  font-family: Helvetica;
}

html,
body,
#map {
  height: 100%;
  width: 100vw;
}

.sss {
  display: block;
  position: absolute;
  top: 20px;
  left: calc(50% - 100px);
  text-align: center;
  background: #fff;
  padding: 15px 0px;
  z-index: 9999;
  color: #000;
  width: 200px;
  box-shadow: 0px 5px 50px #000;
}

.sss.ok {
  color: red;
  font-weight: bold;
}

JavaScript

$(function() {

  var mymap = L.map('map').setView([51.67204, 39.1843], 12);
  L.tileLayer('https://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png', {
    maxZoom: 18,
    attribution: '<a href="https://www.openstreetmap.org/">OpenStreetMap</a>'
  }).addTo(mymap);
  
	ticount = 0;
	mymap.on('move', function() {
		ticount += 1;
    
		$('.sss').text(ticount);
    
		if(ticount==50) {
			$('.sss').addClass('ok');
		}
    
	});

});