JSFiddle - React, Tailwind, and code Playground

HTML

<div class="wrapper">
    <div class="top">top</div>
    <div class="left">left</div>
    <div class="content">
        content<br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br />end
    </div>
</div>

CSS

.wrapper {
    padding: 100px 0 0 100px;
}

.top {
    top: 0;
    left: 0;
    position: fixed;
    width: 100%;
    height: 100px;
    background-color: #fc0;
}
.left {
    top: 100px;
    left: 0;
    position: fixed;
    width: 100px;
    height: 100%;
    background: green;
}