<div class="parent">
  <div class="child center">Center</div>
  <div class="child left">Left</div>
  <div class="child right">Right</div>
</div>
* {
  margin: 0;
  padding: 0;
}
body {
  margin: 2em;
}



.child {
  display: flex;
  justify-content: center;
  align-items: center;
  height: 200px;
  color: #fff;
  font-size: 1.4rem;
}
.left {
  background: #e74c3c;
}
.center {
  background: #3498db;
}
.right {
  background: #f39c12;
}
@media (min-width:768px) {
  .child:not(.center) {
    width: 150px;
  }
  .parent {
    display: flex;
  }
  .left {
    order: 1;
  }
  .center {
    flex: 1;
    order: 2;
  }
  .right {
    order: 3;
  }
}

External CSS

  1. https://fonts.googleapis.com/css?family=Open+Sans:400,300

External JavaScript

This Pen doesn't use any external JavaScript resources.