JSFiddle - React, Tailwind, and code Playground

HTML

<div id="div1">
    <div id="divA">
        Lorem ipsum
    </div>
    
    <div id="divB">
        Lorem ipsum bla bllkfdkl;lahsd;fkha;fha;fdjhsfa bla bla bla
    </div>
</div>

CSS

#div1 {
    width:300px;
    height:20px;
    position:relative;
}

#divA {
    height:100%;
    border:1px solid black;
    background:white;
    padding:2px;
}

#divB {
    height:100%;
    position:absolute;
    border:1px solid black;
    background:white;
    padding:2px;
    top:0;
    right:0;
}