<div class="danger">
  <h2>
 My flex-direction and background color change with the viewport size!
  </h2>
   <h2>
    My flex-direction and background color change with the viewport size!
  </h2>
   <h2>
    My flex-direction and background color change with the viewport size!
  </h2>
</div>

/** Styles when > media query */

.danger {
  background: orange;
  display: -webkit-box;
  display: -ms-flexbox;
  display: flex;
  font-family: sans-serif;
  padding-left: 1em;
}

@media (max-width: 600px) {
  /* styles for small viewport */
  .danger {
    -webkit-box-orient: vertical;
    -webkit-box-direction: normal;
    -ms-flex-direction: column;
    flex-direction: column;
    background-color: rgb(102, 51, 153);
  }
}

@media (min-width: 600px) and (max-width: 1280px) {
  .danger {
    display: -webkit-box;
    display: -ms-flexbox;
    display: flex;
    -ms-flex-pack: distribute;
    justify-content: space-around;
    padding: 1rem;
    background: teal;
  }
}