<!-- note that the answers must fit on the back of the card or they will overflow -->
<div class="flip-card">
  <div class="flip-card-inner">
    <div class="flip-card-front">
      <h2>Question 1</h2>
      <p>This is a question about something or other</p>
      <p class="flipme">(Hover card to see answer)</p>
    </div>
    <div class="flip-card-back">
      <h2>Answer 1</h2>
      <p>The answer is that I don't know what the question means</p>
    </div>
  </div>
</div>

<div class="flip-card">
  <div class="flip-card-inner">
    <div class="flip-card-front">
      <h2>Question 2</h2>
      <p>This is a longer question about something or other that you need to answer.</p>
      <p class="flipme">(Hover card to see answer)</p>
    </div>
    <div class="flip-card-back">
      <h2>Answer 2</h2>
      <p>The answer is once again that I don't know the answer and I still don't know what the question means</p>
    </div>
  </div>
</div>

.flip-card h2 {
  margin: 0 0 1rem;
}
.flip-card {
  width: 300px;
  perspective: 1000px;
  margin: 1rem;
}

.flip-card-inner {
  position: relative;
  width: 100%;
  height: 100%;
  text-align: center;
  transition: transform 0.8s;
  transform-style: preserve-3d;
}

.flip-card:hover .flip-card-inner {
  transform: rotateY(180deg);
}

.flip-card-front,
.flip-card-back {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  padding: 10px;
  -webkit-backface-visibility: hidden;
  backface-visibility: hidden;
  box-shadow: 0 0 10px rgba(0, 0, 0, 0.7);
}

.flip-card-front {
  background-color: teal;
  color: white;
  position: static;
}
.flip-card-back {
  background-color: black;
  color: white;
  transform: rotateY(180deg);
}

/*

Forum question answer only :

https://www.sitepoint.com/community/t/transactions-and-animations/377584/5

*/