body {
  height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
}

a {
  text-decoration: none;
  color: #262626;
  font-family: sans-serif;
  font-size: 40px;
  border: 3px solid #262626;
  padding: 40px 80px;
  transition: all 0.5s;
  position: relative;
  overflow: hidden;
}

a::before {
  content: "Hover me";
  position: absolute;
  top: 0;
  left: 0;
  height: 100%;
  width: 100%;
  background-color: #262626;
  color: white;
  display: flex;
  justify-content: center;
  align-items: center;
  transform: scale(5);
  opacity: 0;
  transition: all 0.5s;
}
a:hover::before {
  transform: scale(1);
  opacity: 100;
}