JSFiddle - React, Tailwind, and code Playground

HTML

<div id="container">
    <div id="divA">
        <p>This div will scroll.</p>
    </div>
    <div id="divB">
        <p>This div will not scroll.</p>
    </div>
</div>

CSS

#container {
    height: 100%;
    postition: relative;
    width: 100%;
}

#divA {
    background: #ccc;
    height: 100px;
    left: 0;
    position: absolute;
    top: 0;
    width: 1000px;
    padding-top:100px;
}

#divB {
    background: #c55;
    height: 100px;
    position: fixed;
    right: 0;
    width: 100%;
}