<div class="move-to-center">
  <div class="original-position">
    <button>HOVER TOP AND FLICKER</button>
  </div>
</div>

body {
  margin: 0;
}

.move-to-center {
  display: flex;
  justify-content: center;
  align-items: center;
  flex-direction: column;
  height: 100vh;
}

.move-to-center {
  margin-top: 10px;
}

button {
  position: relative;
  font: 3rem Lato, sans-serif;
  background-color: black;
  color: white;
  border: none;
  height: 100px;
}

button:hover {
  margin-top: 50px;
}

.original-position {
  border: 3px solid red;
  height: 100px;
}