<!DOCTYPE html>
<html lang="ko">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>가운데정렬</title>
</head>
<body>
  <div class="parents">
    <div class="children">Children</div>
  </div>
</body>
</html>
.parents {
  background-color: dodgerblue;
  width: 200px;
  height: 200px;
  margin: 0 auto;
  text-align: center;
}

.children {
  background-color: orange;
  width: 100px;
  height: 100px;
  margin: 0 auto;
}

External CSS

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External JavaScript

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