html, body {
  margin: 0;
  width: 100%;
  height: 100%;
  display: flex;
  background-color: #000;
}

button {
  margin: auto;
  padding: 20px 50px;
  background: none;
  border-radius: 5px;
  outline: none;
  border: 1px solid #000;
  position: relative;
  overflow: hidden;
}

button span {
  position: relative;
  z-index: 3;
  color: yellowgreen;
}

button::after {
  content: '';
  position: absolute;
  left: calc(50% - 25px);
  top: 50%;
  width: 50px;
  height: 150px;
  background-color: orange;
  z-index: 1;
  transform-origin: 50% 0;
  animation: move 3s linear infinite;
}

button::before {
  content: '';
  position: absolute;
  width: calc(100% - 4px);
  height: calc(100% - 4px);
  left: 2px;
  top: 2px;
  background-color: #000;
  border-radius: 5px;
  z-index: 2;
}

@keyframes move {
  0% {
    transform: rotate(0);
  }
  100% {
    transform: rotate(360deg);
  }
}