JSFiddle - React, Tailwind, and code Playground

HTML

<div id="container">   

    <div class="box" id="bluebox">
        <p>DIV #1</p>
    </div>

    <div class="box" id="redbox">
        <p>DIV #2</p>
    </div>
    
</div>

CSS

#container {
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    height: 300px;
    border: 1px solid black; /* for demo purposes */
}

.box {
    width: 300px;
    margin: 5px;
    text-align: center;
}

#bluebox {
    background: aqua;
}

#redbox {
    background: red;
}