button

button hover

HTML

<button>
BUY 
</button>

CSS

body {
  background-color: black
}

button {
 position: relative;

  color: black;
  font-size: 1.625rem;

  background-color: yellow;
  border: 1px solid white;

  padding: 15px 50px;

  cursor: pointer;
}

button::after {
  content: "";
  position: absolute;
  left: 0.8rem;
  top: 0.8rem;

  width: 100%;
  height: 100%;

  background: transparent;
  border: 1px solid white;

  transition: all 0.3s;

  z-index: -1;
}