Thingie

HTML

<flex-container>
  <flex-center-content>

	    <flex-item></flex-item>
	    <flex-item></flex-item>
	    <flex-item></flex-item>

  </flex-center-content>
    <flex-footer>
      this is the footer element<br />
      this is the footer element<br />
      this is footeeeeer<br>
      look how tall I am<br>
      and how much I push things<br>
    </flex-footer>
</flex-container>

CSS

flex-container {
    display: flex;
    flex-direction:column;
    align-items: center;
    justify-content:flex-end;
    border: 4px solid blue;
    height: 300px;
    width: 300px;
}

flex-container > flex-center-content {
    display:flex;
    height:100%;
    width:100%;
    align-items:center;
    justify-content:center;
    flex-direction:row;
}

flex-container > flex-footer {
    border: 4px solid chartreuse;
}

flex-container > flex-center-content > flex-item {
    border: 4px solid aqua;
    height: 50px;
    width: 50px;
    margin: 0 5px;
}