JSFiddle - React, Tailwind, and code Playground

HTML

<div class="grid-table">
  <span>Room Name</span>
  <span>Start Date</span>
  <span>End Date</span>
  
  <span>Room 100</span>
  <span>Tuesday</span>
  <span>Wednesday</span>
  
  <span>Room 200</span>
  <span>Tuesday</span>
  <span>Friday</span>
  
  <span>Room 200</span>
  <span>Tuesday</span>
  <span>Friday</span>
  
  <span>Room 200</span>
  <span>Tuesday</span>
  <span>Friday</span>
</div>

CSS

.grid-table {
  display:grid;
  display: -ms-grid;
  
  grid-template-columns: repeat(3, auto);
  -ms-grid-template-columns: repeat(3, auto);
}

.grid-table :nth-child(-n+3) {
  background-color:red;
}