CSS Columns Question

HTML

<div class="takeremaining">
  <div class="centeredcontent">
  This is my centered content
  </div>
</div>
<div class="dynamicallyallocated">
  This is my dynamic content
</div>

CSS

.takeremaining {
  display: inline-block;
  width: 100%;
  float: left;
  background-color: #0000ff;
}

.centeredcontent {
  display: table;
  margin: 0 auto;
  background-color: #00ffff;
}

.dynamicallyallocated {
  display: inline-block;
  float: right;
  background-color: #00ff00
}