<div class="center">
  <div class="btn-1">
    <p>Button 1: </p>
    <a href=""><span>Hover over me</span></a>
  </div>
  <!-- Created by   http://grohit.com/   -->
  <div class="btn-2">
    <p>Button 2: </p>
    <a href=""><span>Hover over me</span></a>
  </div>
</div>

<footer>
<a href="https://codepen.io/grohit/" target="_blank">Check out My other pens</a>
</footer>

body {
  background: #ffffff;
  font-family: "Gill Sans", "Gill Sans MT", Calibri, "Trebuchet MS", sans-serif;
  color: #c2c2c2;
}

.center {
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 100vh;
  font-size: 24px;
}

.btn-1,
.btn-2 {
  width: 300px;
  height: 200px;
  display: flex;
  justify-content: center;
  align-items: center;
  flex-direction: column;
}
/* Created by http://grohit.com/  */
footer a,
.btn-1 a,
.btn-2 a {
  text-decoration: none;
  border: 2px solid #010100;
  padding: 15px;
  color: #000;
  text-transform: uppercase;
  letter-spacing: 2px;
  position: relative;
  display: inline-block;
}

span {
  position: relative;
  /* z-index coz when we put bg to before and after this span text will not be visible */
  z-index: 3;
}

/* Button 1 styles */

.btn-1 a::before {
  content: "";
  position: absolute;
  top: 5px;
  left: -2px;
  width: calc(100% + 6px);
  /*100% plus double the times left values*/
  height: calc(100% - 10px);
  background-color: #ffffff;
  transition: all 0.5s ease-in-out;
  transform: scaleY(1);
}

.btn-1 a:hover::before,
.btn-2 a:hover::before {
  transform: scaleY(0);
}

.btn-1 a::after {
  content: "";
  position: absolute;
  left: 5px;
  top: -5px;
  width: calc(100% - 10px);
  /*100% plus double the times left values*/
  height: calc(100% + 10px);
  background-color: #ffffff;
  transition: all 0.5s ease-in-out;
  transform: scaleX(1);
}
/* Created by http://grohit.com/  */

.btn-1 a:hover::after,
.btn-2 a:hover::after {
  transform: scaleX(0);
}

/* Button 2 styles */

.btn-2 a {
  color: #ffffff;
  transition: all 0.5s ease-in-out;
}

.btn-2 a:hover {
  color: #000000;
  transition: all 0.5s ease-in-out;
}

.btn-2 a::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: #000;
  transition: all 0.5s ease-in-out;
  transform: scaleY(1);
}

.btn-2 a::after {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  width: 100%;
  height: 100%;
  background-color: black;
  transition: all 0.5s ease-in-out;
  transform: scaleX(1);
}

/* Created by http://grohit.com/  */
footer{
    text-align: center;
  font-size: 10px;
}