JSFiddle - React, Tailwind, and code Playground

HTML

<div class="container">
    <div class="box1">Box 1</div>
    <div class="box2">Box 2</div> 
    <div style="clear:both;"></div>
</div>

CSS

.container {height:auto; background:yellow; display:block; float:left; padding:40px 0; width:100%;}
.box1 {position:fixed; background:red; height:300px;}
.box2 {position:absolute; background:green; margin-top:20px; height:200px;}