JSFiddle - React, Tailwind, and code Playground

HTML

<body>
    <table id="newTable">
        <tr>
            <td class="test"><span id="first"> </span></td>
            <td class="test"><span id="second"> </span> </td>
        </tr>
        <tr>
            <td class="test"><span id="third"> </span> </td>
            <td class="test"><span id="four"> </span> </td>
        </tr>
        <tr>
            <td class="test"><span id="five"> </span> </td>
            <td class="test"><span id="six"> </span> </td>
        </tr>
        <tr>
            <td class="test"><span id="seven"> </span> </td>
            <td class="test"><span id="eight"> </span> </td>
        </tr>
    </table>
</body>
    <script src="script.js"></script>

CSS

td {
    border: solid;
    width: 120px;
    height: 120px;
    border-collapse: collapse;
}

span {
    display: none;
}

table {
    font-size: 50px;
    text-align: center;
    border-collapse: collapse;
    background-color: #66ff66;
}

JavaScript

"use strict"
/**
 *
 * Created by anton on 14.05.16.
 */

var numbers = [1,1,2,2,3,3,4,4];

var firstNode = document.getElementById('first');
var secondNode = document.getElementById('second');
var thirdNode = document.getElementById('third');
var fourNode = document.getElementById('four');
var fiveNode = document.getElementById('five');
var sixNode = document.getElementById('six');
var sevenNode = document.getElementById('seven');
var eightNode = document.getElementById('eight');

Array.prototype.shuffle = function() {
    return this.sort(function() {
        return 0.5 - Math.random();
    });
};

numbers.shuffle();

firstNode.innerHTML = numbers[0];
secondNode.innerHTML = numbers[1];
thirdNode.innerHTML = numbers[2];
fourNode.innerHTML = numbers[3];
fiveNode.innerHTML = numbers[4];
sixNode.innerHTML = numbers[5];
sevenNode.innerHTML = numbers[6];
eightNode.innerHTML = numbers[7];

var newArray = [];

function showNumber(event) {
    event.target.firstChild.style.display = 'inline';
    newArray.push( event.target.firstChild.innerHTML);
   if (newArray.length === 2) {
       if (newArray[0] !== newArray[1]) {
           for(var i = 0; i < variables.length; i++) {
               if (variables[i].children[0].innerHTML === newArray[0] || newArray[1]) {
                   variables[i].children[0].style.display = '';
               }
           }
           newArray.length = 0;
           console.log(newArray.length)
       }
       newArray.length = 0;
       console.log(newArray.length)

   }
}

var variables = document.querySelectorAll('.test');
[].forEach.call(variables, function(variable){
   variable.addEventListener("click", showNumber);
});