JSFiddle - React, Tailwind, and code Playground

HTML

<p>Resize preview window to see what this is doing.</p>
<div class="flex-container">
  <div class="flex-item">1</div>
  <div class="flex-item">2</div>
  <div class="flex-item">3</div>
  <div class="flex-item">4</div>
  <div class="flex-item">5</div>
</div>

CSS

.flex-container {
    background-color: #000;
    height: 100%;
    display:flex;
    flex-direction: row;
    flex-wrap: wrap;
    justify-content: flex-start;
    align-content: stretch;
    align-items: stretch;
}

.flex-item {
    background-color: #ccf;
    margin: 0.1em;
    flex-grow: 1;
    flex-shrink: 0;
    flex-basis: 150px; /* or % could be used to ensure a specific layout */
}