body {
  width: 100%;
  height: 100vh;
  margin: 0;
  display: flex;
  justify-content: center;
  align-items: center;
}

.wrap {
  width: 80%;
  height: 80%;
  background-color: #fff;
  border: 1px solid #999;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
}

img {
  display: block;
  margin: 0 auto;
}

.btns {
  margin-top: 50px;
}

button {
  width: 120px;
  padding: 12px 24px;
  font-size: 24px;
  color: #fff;
  cursor: pointer;
}

button:hover {
  opacity: 0.9;
}

#startBtn {
  background-color: #2e7d32;
  margin-right: 10px;
}

#stopBtn {
  background-color: #c62828;
}

@keyframes rotate {
  0% {
    transform: rotate(0deg) scale(1);
  }
  25% {
    transform: rotate(90deg) scale(1.1);
  }
  50% {
    transform: rotate(180deg) scale(1.2);
  }
  75% {
    transform: rotate(270deg) scale(1.1);
  }
  100% {
    transform: rotate(360deg) scale(1);
  }
}

img {
  width: 200px;
}

img.start {
  animation: rotate 5s linear infinite;
  transform-origin: center;
  animation-play-state: running;
}

img.paused {
  animation-play-state: paused;
}