button {
  cursor: pointer;
  background-color: transparent;
  color: white;
  border: none;
  font-size: 17px;
  position: relative;
  z-index: 3;
  transition: 0.5s;
  -webkit-transition: 0.5s;
  -moz-transition: 0.5s;
  -ms-transition: 0.5s;
  -o-transition: 0.5s;
}

button::before {
  content: "";
  border: 3px solid white;
  position: absolute;
  left: -25px;
  bottom: 0;
  display: block;
  width: 10px;
  height: 10px;
  border-radius: 60px;
  -webkit-border-radius: 60px;
  -moz-border-radius: 60px;
  -ms-border-radius: 60px;
  -o-border-radius: 60px;
  transition: 0.5s;
  -webkit-transition: 0.5s;
  -moz-transition: 0.5s;
  -ms-transition: 0.5s;
  -o-transition: 0.5s;
}

button:hover::before {
  left: -25px;
  bottom: -17.5px;
  width: 100%;
  padding: 20px;
  background-color: white;
  z-index: -1;
}

button:hover {
  color: #282828;
}