JSFiddle - React, Tailwind, and code Playground

CSS

.level_begin_label{
	position: absolute;
	top: 0;
	left: 0;
	right: 0;
	bottom: 0;
	z-index: 1000;
	background: #000;
	padding-top: 20px;

	color: #fff;
	text-align: center;
	font: 20px arial, sans-serif;
}

	.any_key_invitation{
		margin-top: 10px;

		font-size: 16px;
	}
  
.game{
/*	position: absolute;
	top: 0;
	left: 0;
	right: 0;
	bottom: 0;*/
	z-index: 10;
	position: relative;
	background: #000;
	width: 300px;
	height: 100%;
	margin: 0 auto;
	padding-top: 40px;

	color: #fff;
}

JavaScript

var Game = function(parentGameElementTag) {
  this.parentGameElementTag = parentGameElementTag;
  this.gameElementId = 'game';
  this.levelObj = new Level();  

  this.init();
};

Game.prototype = {
  init: function() {  
    $('<div class="game" id="' + this.gameElementId + '"></div>').appendTo(this.parentGameElementTag);   
  }
 };
 
 var Level = function() { 
  var self = this;

  this.fieldElementId = 'field';  
  this.levelScreenDisplay('body');  
};

//Level.prototype = Game;
Level.prototype = Object.create(Game.prototype);

Level.prototype = {

  levelScreenDisplay: function(parentElementTag) {
    $('<div class="level_begin_label" id="levelBeginLabel">Уровень: ' + this.level + '</div>').appendTo(parentElementTag);   

    setTimeout(function() { 
      $('<div class="any_key_invitation" id="anyKeyInvitation">Нажмите любую клавишу для старта</div>').appendTo('#levelBeginLabel');

      document.onkeypress = function() {
        document.onkeypress = undefined;
        $('#levelBeginLabel').remove();
      };          
    }, 1000);
  }
};
 
var	app = new Game('body');