JSFiddle - React, Tailwind, and code Playground

HTML

<div id="grid">
  <div class="cell">
  </div>

  <div class="cell">
  </div>

  <div class="cell">
  </div>

  <div class="cell">
  </div>
</div>

CSS

#grid {
  display: grid;
  grid-template-columns: auto auto;
  grid-gap: 2px;
  width: 200px;
  height: 200px;
}

.cell{
  background: grey;
}

JavaScript

$(function(){
	var rowSize =$(".cell").first().css("grid-row").split('/').length
  $(".cell").each((c,elem)=>{
  	elem.innerText= Math.ceil(++c / rowSize)
  })
})