JSFiddle - React, Tailwind, and code Playground

HTML

<div class="Buttons">
    <div id="element1">
        Button1

            <div class="redCircle">1</div>
            <div class="greenCircle">2</div>

    </div>
           
</div>
<div class="Buttons">
    <div id="element2">
        Button2

            <div class="redCircle">3</div>
            <div class="greenCircle">4</div>
        

    </div>
</div>

CSS

#element1 {
        width: 150px;
        height: 150px;
        margin: 10px;
        background-color: red;
        display: block;
    }
    
    #element2 {
        width: 150px;
        height: 150px;
        margin: 10px;
        background-color: green;
    }


    .redCircle{
        width: 50px;
    height: 50px;
    border: 1px solid white;
    border-radius: 50%;
    background-color: red;
    font-size: 1.5em;
    text-align: center;
    vertical-align: middle;
    color:white;
    display: none;
}

    .greenCircle {
    width: 50px;
    height: 50px;
     border: 1px solid white;
    border-radius: 50%;
    background-color: green;
    text-align: center;
    vertical-align: middle;
    font-size: 1.5em;
    color:white;
}

.show {
         display: block;
    }

JavaScript

var buttonClick = document.getElementsByClassName('Buttons'); 
var redCircle = document.getElementsByClassName('redCircle');
var greenCircle = document.getElementsByClassName('greenCircle');
// Реализация событий по клику мышки

    for (i=0; i< buttonClick.length; i++){
    buttonClick[i].onclick= function() { 
       // for (var j = 0; j < redCircle.length; j++) {
       //     redCircle[j].style.display ='block';
       // }
       
        redCircle.classList.toggle('show', false)

    };


}