<section class="grid">
  <div class="item">item1</div>
  <div class="item">item2</div>  
</section>

.grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  grid-template-rows: 100px 100px;
  grid-auto-columns: 200px;
  grid-auto-rows: 60px;
  grid-gap: 20px;
  max-width: 800px;
}


.item:first-child {
  grid-row-end: 2;
  grid-row-start: span 2;
}

.item:nth-child(2) {
  grid-column-end: 2;
  grid-column-start: span 2;
}