<div class="container">
  <div class="item item1">1</div>
  <div class="item item2">2</div>
  <div class="item item3">3</div>
  <div class="item item4">4</div>
  <div class="item item5">5</div>
  <div class="item item6">6</div>
  <div class="item item7">7</div>
  <div class="item item8">8</div>
  <div class="item item9">9</div>
  <div class="item item10">10</div>
</div>
.container {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(100px, 1fr));
  gap: 10px;
}

.item {
  padding: 2em;
  border: 2px solid black;
  background-color: rebeccapurple;
  color: white;
  display: flex;
  flex-flow: row;
  place-content: center;
  align-items: center;
}

External CSS

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External JavaScript

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