<input id="rotation-checkbox" type="checkbox" class="rotator"> <label for="rotation-checkbox">rotate</label>
<br>
<section role="region" aria-hidden="true" aria-label="Taichi" class="taichi-container">
  <div class="taichi-white"></div>
  <div class="taichi-black"></div>
</section>

.taichi-container {
  position: relative;
  display: inline-block;
  width: 200px;
  height: 200px;
  border: solid 2px black;
  /* For some browsers, it may have insufficient radius issue. We use over-radius tricks to fix it */
  border-radius: 60%;
  background-color: black;
}

.taichi-white {
  width: 50%;
  height: 100%;
  display: inline-block;
  position: absolute;
  left: 0;
  top: 0;
  background-color: white;
  border: solid 0 white;
  box-sizing: border-box;
  border-top-left-radius: 100% 50%;
  border-bottom-left-radius: 100% 50%;
}

.taichi-white:before {
  content: ' ';
  width: 100%;
  height: 50%;
  background-color: white;
  display: inline-block;
  position: absolute;
  left: 50%;
  border-radius: 60%;
}

.taichi-white:after {
  content: ' ';
  width: 10%;
  height: 5%;
  background-color: black;
  display: inline-block;
  position: absolute;
  left: 95%;
  top: 22.5%;
  border-radius: 60%;
}

.taichi-black {
  width: 50%;
  height: 50%;
  display: inline-block;
  position: absolute;
  left: 50%;
  bottom: 0;
  background-color: black;
  border: solid 0px black;
  box-sizing: border-box;
  border-bottom-right-radius: 100%;
}

.taichi-black:before {
  content: ' ';
  width: 100%;
  height: 100%;
  background-color: black;
  display: inline-block;
  position: absolute;
  left: -50%;
  bottom: 0%;
  border-radius: 60%;
}

.taichi-black:after {
  content: ' ';
  width: 10%;
  height: 10%;
  background-color: white;
  display: inline-block;
  position: absolute;
  left: 0;
  bottom: 50%;
  border-radius: 60%;
}

.rotator:checked ~ .taichi-container {
  animation: rotate-animation 4s linear infinite;
  animation-play-state: play;
}

.rotator ~ .taichi-container {
  animation: rotate-animation 4s linear infinite;
  animation-play-state: paused;
}

@keyframes rotate-animation {
  100% {
    transform: rotate(360deg);
  }
}