<div class="box">
  <div class="item"><span>275px</span></div>
  <div class="item"><span>275px</span></div>
  <div class="item"><span>275px</span></div>
</div>
body {
  padding: 16px;
  font-family: monospace;
  font-size: 15px;
  line-height: 120px;
  text-align: center;
}

.box {
  height: 100px;
  display: grid;
  grid-template-areas: "a a";
  grid-gap: 16px;
  grid-auto-columns: 275px;
}

.item {
  background-color: #f7f7f7;
  outline: 4px solid #555;
}

External CSS

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External JavaScript

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