animation-direction CSS property

animation-direction: normal;

animation-direction: reverse;

animation-direction: alternate;

animation-direction: alternate-reverse;

<section class="flex-column" id="default-example">
  <div id="example-element"></div>
  <button id="play-pause">Play</button>
</section>

#example-element {
  animation-duration: 3s;
  animation-iteration-count: infinite;
  animation-name: slide;
  animation-play-state: paused;
  animation-timing-function: ease-in;
  background-color: #1766aa;
  border-radius: 50%;
  border: 5px solid #333333;
  color: white;
  height: 150px;
  margin: auto;
  margin-left: 0;
  width: 150px;
}

#example-element.running {
  animation-play-state: running;
}

#play-pause {
  font-size: 2rem;
}

@keyframes slide {
  from {
    background-color: orange;
    color: black;
    margin-left: 0;
  }
  to {
    background-color: orange;
    color: black;
    margin-left: 80%;
  }
}

const el = document.getElementById("example-element");
const button = document.getElementById("play-pause");

button.addEventListener("click", () => {
  if (el.classList.contains("running")) {
    el.classList.remove("running");
    button.textContent = "Play";
  } else {
    el.classList.add("running");
    button.textContent = "Pause";
  }
});

/* Single animation */
animation-direction: normal;
animation-direction: reverse;
animation-direction: alternate;
animation-direction: alternate-reverse;

/* Multiple animations */
animation-direction: normal, reverse;
animation-direction: alternate, reverse, normal;

/* Global values */
animation-direction: inherit;
animation-direction: initial;
animation-direction: revert;
animation-direction: revert-layer;
animation-direction: unset;

<div class="box"></div>

.box {
  background-color: rebeccapurple;
  border-radius: 10px;
  width: 100px;
  height: 100px;
}

.box:hover {
  animation-name: rotate;
  animation-duration: 0.7s;
  animation-direction: reverse;
}

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