How to knock out a block from a flow in flexbox?

Question

css

How to knock out the third block to the bottom frame, and so that the fourth one is automatically pressed to the second one (when the third one is eliminated)?
https://codepen.io/anon/pen/JZwVdw

Answer 1

https://codepen.io/notfair/pen/YvBKZV?editors=1100
right?

Answer 2

https://developer.mozilla.org/ru/docs/Web/CSS/alig...
https://developer.mozilla.org/ru/docs/Web/CSS/marg...

3 {
  align-self: flex-end;
}

4 {
  margin-left: auto;
}