Align content to bottom when using flex

I have this basic layout with a static header and footer, pushed to the top and bottom respectively. The content section in the middle fills the space, and there’s a scrollbar for this section in case the content is too large for it to fit.

<div id="app">
  <div id="header">
    Header
  </div>

  <div id="middle">
    Middle content
  </div>

  <div id="footer">
    Footer
  </div>
</div>

html,
body {
  height: 100%;
  overflow: hidden;
  margin: 0;
}

#app {
  display: flex;
  flex-direction: column;
  height: 100%;
  overflow: hidden;
}

#header {
  height: 60px;
  background-color: blue;
}

#footer {
  height: 60px;
  background-color: red;
}

#middle {
  flex: 1;
  overflow-y: scroll;
  align-items: flex-end;
}

jsfiddle here.

I want the content of this middle section to start from the bottom, and not the top, while keeping the overflow scrollbars in case the content is too big, but I can’t seem to figure out how.

I’ve tried setting margins to 0 and read about flex-direction, but none of those seem to work.

>Solution :

You can try the following :

  <div id="header">
    Header
  </div>

  <div id="middle" class="content-end">
    Middle content
  </div>

  <div id="footer">
    Footer
  </div>
</div> 

Please add this in your css:

.content-end
{
  display: flex;
  justify-content: start; 
}