<ul class="flex-container">
  <li class="flex-item">1<br>2</li>
  <li class="flex-item">3</li>
  <li class="flex-item">4<br>5</li>
  <li class="flex-item flex-end">6</li>
</ul>
.flex-container {
  padding: 0;
  margin: 0;
  list-style: none;
  height: 200px;
  display: flex;
  align-items:flex-start;
}
.flex-item {
  background: tomato;
  padding: 5px;
  width: 100px;
  margin: 5px;
  
  line-height: 100px;
  color: white;
  font-weight: bold;
  font-size: 2em;
  text-align: center;
}
.flex-end{
  align-self:flex-end;
  margin-bottom:0;
}

External CSS

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External JavaScript

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