<div class="container-flex-wrap">
  <div class="item">Item 1</div>
  <div class="item">Item 2</div>
  <div class="item">Item 3</div>
  <div class="item">Item 4</div>
  <div class="item">Item 5</div>
  <div class="item">Item 6</div>
  <div class="item">Item 7</div>
  <div class="item">Item 8</div>
  <div class="item">Item 9</div>
  <div class="item">Item 10</div>
  <div class="item">Item 11</div>
  <div class="item">Item 12</div>
</div>
<br>
.container-flex-wrap {
  display: flex;
  flex-wrap: wrap;
  flex-direction: row;
  /*flex-flow: row wrap;*/
}
.item {
  background-color: lightblue;
  margin: 5px;
  padding: 5px;
}

External CSS

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External JavaScript

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