CodePen Embed - 012 Spacing

<div>
  <div class="p1"></div>
  <div class="p2"></div>
</div>

div {
  display: flex;
}
.p1,
.p2 {
  height: 100px;
  width: 100px;
  background: black;
  margin: 10px;
  padding: 10px;
}

.p1 {
  box-sizing: border-box;
}

.p2 {
  box-sizing: content-box;
}

This Pen is owned by Pengfei Wang on CodePen.

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