JSFiddle - React, Tailwind, and code Playground

HTML

<div class="container">
<div class="section1">
Top
</div>
<div class="section2">
bottom
</div>
</div>

CSS

@media (max-width: 600px) {
  
.container {
  display:flex;
  flex-direction: column-reverse;
}

.section1,
.section2 {
  height: auto;
}
}