<div class="area-one">
    Lorem ipsum dolor sit amet, consectetur adipisicing elit. Impedit reprehenderit culpa sunt magnam dolores pariatur qui error similique itaque accusamus. Quisquam voluptates sit veritatis eos!
</div>

<div class="area-two">
  Lorem ipsum dolor sit amet, consectetur adipisicing elit. Impedit reprehenderit culpa sunt magnam dolores pariatur qui error similique itaque accusamus. Quisquam voluptates sit veritatis eos!
</div>

.area-one {
  width: 40%;
  float: left;
  height: 100%;
  margin-right: 1em;
  padding: 30px;
  background: red;
  color: white;
}

.area-two {
  width: calc(60% - 1em);
  float: right;
  height: 100%;
  padding: 30px;
  color: white;
  background: blue;
}

html, body {
  height: 100%;
  background: #ccc;
  padding: 20px;
}
body {
  padding: 20px;
  background: white;
}
* {
  box-sizing: border-box;
}