<div class="wrap">
  <div class="item">1</div>
  <div class="item">2</div>
  <div class="item">3</div>
</div>
.wrap {
  display: flex;
  flex-wrap: wrap-reverse;
  width: 220px;
  justify-content: center;
}

.item {
  background: #ccc;
  width: 100px;
  height: 100px;
  text-align: center;
  padding-top: 35px;
  box-sizing: border-box;
  font-weight: bold;
  border: 1px solid #000;
}

.item:first-of-type {
  order: 3;
  margin-bottom: 10px;
}

.item:nth-of-type(2) {
  margin-right: 10px;
}

External CSS

This Pen doesn't use any external CSS resources.

External JavaScript

This Pen doesn't use any external JavaScript resources.