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    <h1>Post Title</h1>
    <p>Some post content</p>
    <p>If you resize the browser window to less than 650px, flexbox will kick in and flip the order of the heading and post content.</p>



                // Use Modernizr to only style for
// supporting browsers
.flexbox {
  article {
    // using -prefix-free to handle
    // vendor prefixing
    // on small screens, use flexbox
    // to flip the post header and content
    display: flex;
    flex-direction: column;
    flex-wrap: wrap;
    // at screen sizes above this
    // don't use flebox
    @media only screen and (min-width: 650px) {
      display: block;
  header {
    order: 2;
  section {
    order: 1;
    // this was required to prevent
    // the element from collapsing.
    width: 100%;