<div class="grid">
  <div class="box item1">Item 1</div>
  <div class="box item2">Item 2</div>
  <div class="box item3">Item 3</div>
  <div class="box item4">Item 4</div>
</div>
.grid {
  display: -ms-grid;
  display: grid;
  -ms-grid-columns: 1fr 1fr 1fr 1fr;
  grid-columns: 1fr 1fr 1fr 1fr;
  -ms-grid-rows: 4fr;
  grid-rows: 4fr;
}

.box {
  background-color: #444;
  color: #fff;
  border-radius: 5px;
  padding: 20px;
  font-size: 150%;
}

.item1 {
  -ms-grid-column: 1;
  grid-column: 1;
  -ms-grid-row: 1;
  grid-row: 1;
  background: #f00;
}
.item2 {
  -ms-grid-column: 2;
  grid-column: 2;
  -ms-grid-row: 1;
  grid-row: 1;
  background: #f0f;
}
.item3 {
  -ms-grid-column: 3;
  grid-column: 3;
  -ms-grid-row: 1;
  grid-row: 1;
  background: #008000;
}
.item4 {
  -ms-grid-column: 4;
  grid-column: 4;
  -ms-grid-row: 1;
  grid-row: 1;
  background: #000;
}

External CSS

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External JavaScript

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