JSFiddle - React, Tailwind, and code Playground

HTML

<div class="container">
  <div>1</div>
  <div>2</div>
  <div>3</div>
  <div class="chief">chief</div>
  <div>4</div>
  <div>5</div>
  <div>6</div>
</div>

CSS

.container {
  display: flex;
  flex-wrap: wrap;
}
.container > div {
  width: 100%;
}
.container > div.chief {
  width: 100%;
}

@media (min-width: 500px) {
  .container > div.chief {
    order: 2;
  }
  .container > div {
    width: 50%;
  }
}

@media (min-width: 1000px) {
  .container > div {
    width: 33.33%;
  }
}


/* --- */

html, body , .container {
  height: 100%;
  margin: 0;
}

.container {
  padding: 20px;
  box-sizing: border-box;
}

.container * {
  outline: 1px solid red;
  display: grid;
  align-items: center;
  justify-content: center;
}