JSFiddle - React, Tailwind, and code Playground

HTML

<div class="container">
  <div class="item"></div>
  <div class="item"></div>
  <div class="item"></div>
  <div class="item"></div>
  <div class="item"></div>
  <div class="item"></div>
  <div class="item"></div>
</div>

CSS

.container {
  background: gray;
  display: flex;
  flex-flow: row wrap;
  position: relative;
  width:100%;
}

.item {
  background: blue;
  width:18%;
  height: auto;
  padding: 4px;
  flex: 1;
  flex-basis: 18%;
  border: 1px solid red;
}