JSFiddle - React, Tailwind, and code Playground

HTML

<div class="wrapper">
<div id="first_div">first div</div>
<div id="second_div">second div</div>
</div>

CSS

#first_div {
    background: yellow;
    /* just to give it some arbitrary height; 
    the height can be dynamic */
    height: 200px; 
}

#second_div {
    background: cyan;
    /* just to give it some arbitrary height; 
    the height can be dynamic */
    height: 300px; 
}