<div class="container">
  <div class="item center"></div>
  <div class="item"></div>
</div>
.container {
  display: flex;
  height: 90vh;
  width: 90vw;
  border: 3px solid black;
  margin: auto;
}

.item {
  width: 20vw;
  padding: 50px;
  background: teal;
  margin: 0 auto;
}

.center {
  align-self: center;
}

External CSS

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External JavaScript

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