[css] How do I center this form in css?

Another way

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body {_x000D_
    text-align: center;_x000D_
}_x000D_
form {_x000D_
    display: inline-block;_x000D_
}
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<body>_x000D_
  <form>_x000D_
    <input type="text" value="abc">_x000D_
  </form>_x000D_
</body>
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