<div class="container">
  <div class="blue-box">
  </div>
  <div class="pink-box">
  <div>
</div>
.container {
  width: 600px;
  border: 4px solid #9be22d;
  overflow: auto;
}

.blue-box {
  float: left;
  width: 200px;
  height: 200px;
  background-color: #66d9ef;
}
.pink-box {
  float: right;
  width: 200px;
  height: 200px;
  background-color: #cc3f85;
}

External CSS

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External JavaScript

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