<div class="container">
  <div class="item item--1">
    Item 1
  </div>
  <div class="item item--2">
    Item 2
  </div>
  <div class="item item--3">
    Item 3
  </div>  
</div>
.item--3 {
  _margin-top: auto; /* Takes precedence */
  align-self: start;
}

/* ETC (Formatting only): */

body {
  margin: 1.5em;
  font-size: 130%;
  font-family: sans-serif;
}

.container {
  border: 5px solid black;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  height: 10em;
}

.item {  
  padding: 1em;
  text-align: center;
  background: lightgrey;
  border-color: black;
  min-height: 5em;
  width: 5em;  
}

.item--3 {
  background: dimgrey;
}

External CSS

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External JavaScript

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