<div class="wrapper">
  <div class="tabs">
    <div class="tab">
      <input type="radio" name="css-tabs" id="tab-1" checked class="tab-switch">
      <label for="tab-1" class="tab-label">Tab One</label>
      <div class="tab-content">My father had a small estate in Nottinghamshire: I was the third of five sons. He sent me to Emanuel College in Cambridge at fourteen years old, where I resided three years, and applied myself close to my studies; but the charge of maintaining me, although I had a very scanty allowance, being too great for a narrow fortune, I was bound apprentice to Mr. James Bates, an eminent surgeon in London, with whom I continued four years. </div>
    </div>
    <div class="tab">
      <input type="radio" name="css-tabs" id="tab-2" class="tab-switch">
      <label for="tab-2" class="tab-label">Tab Two</label>
      <div class="tab-content">My father now and then sending me small sums of money, I laid them out in learning navigation, and other parts of the mathematics, useful to those who intend to travel, as I always believed it would be, some time or other, my fortune to do. </div>
    </div>
    <div class="tab">
      <input type="radio" name="css-tabs" id="tab-3" class="tab-switch">
      <label for="tab-3" class="tab-label">Tab Three</label>
      <div class="tab-content">When I left Mr. Bates, I went down to my father: where, by the assistance of him and my uncle John, and some other relations, I got forty pounds, and a promise of thirty pounds a year to maintain me at Leyden: there I studied physic two years and seven months, knowing it would be useful in long voyages.</div>
    </div>
  </div>
  <p>Example line outside of tab box</p>
</div>

* {
  box-sizing: border-box;
}
body {
  font-family: "Open Sans";
  background: #2c3e50;
  color: #ecf0f1;
  line-height: 1.618em;
}
.wrapper {
  max-width: 50rem;
  width: 100%;
  margin: 0 auto;
}
.tabs {
  position: relative;
  margin: 3rem 0;
  background: #1abc9c;
  height: 14.75rem;
}
.tabs::before,
.tabs::after {
  content: "";
  display: table;
}
.tabs::after {
  clear: both;
}
.tab {
  float: left;
}
.tab-switch {
  display: none;
}
.tab-label {
  position: relative;
  display: block;
  line-height: 2.75em;
  height: 3em;
  padding: 0 1.618em;
  background: #1abc9c;
  border-right: 0.125rem solid #16a085;
  color: #fff;
  cursor: pointer;
  top: 0;
  transition: all 0.25s;
}
.tab-label:hover {
  top: -0.25rem;
  transition: top 0.25s;
}
.tab-content {
  height: 12rem;
  position: absolute;
  z-index: 1;
  top: 2.75em;
  left: 0;
  padding: 1.618rem;
  background: #fff;
  color: #2c3e50;
  border-bottom: 0.25rem solid #bdc3c7;
  opacity: 0;
  transition: all 0.35s;
}
.tab-switch:checked + .tab-label {
  background: #fff;
  color: #2c3e50;
  border-bottom: 0;
  border-right: 0.125rem solid #fff;
  transition: all 0.35s;
  z-index: 1;
  top: -0.0625rem;
}
.tab-switch:checked + label + .tab-content {
  z-index: 2;
  opacity: 1;
  transition: all 0.35s;
}