[CSS Animation] PCPP Loading Boxes

Красивая и не слишком сложная анимация, например, для загрузочной страницы сайта.

HTML

<h1 class="intro">[CSS animation] PCPP Loading Boxes</h1>
<div class="box">
  <div class="cube"></div>
  <div class="cube"></div>
  <div class="cube"></div>
  <div class="cube"></div>
</div>

CSS

.cube {
  position: absolute;
  width: 1em;
  height: 1em;
  background: #FED74C;
  -webkit-animation: move 3s ease-in-out infinite;
          animation: move 3s ease-in-out infinite;
  -webkit-transform-style: preserve-3d;
          transform-style: preserve-3d;
  box-shadow: 5em 5em .3em .1em #DBDBDB;
}
.cube::before, .cube::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
}
.cube::before {
  background-color: #C97431;
  -webkit-transform-origin: 100% 100%;
          transform-origin: 100% 100%;
  -webkit-transform: rotateY(-90deg);
          transform: rotateY(-90deg);
}
.cube::after {
  background-color: #E7A22B;
  -webkit-transform-origin: 0% 100%;
          transform-origin: 0% 100%;
  -webkit-transform: rotateX(90deg);
          transform: rotateX(90deg);
}
.cube:nth-of-type(1) {
  -webkit-animation-delay: -11.25s;
          animation-delay: -11.25s;
}
.cube:nth-of-type(2) {
  -webkit-animation-delay: -10.5s;
          animation-delay: -10.5s;
}
.cube:nth-of-type(3) {
  -webkit-animation-delay: -9.75s;
          animation-delay: -9.75s;
}
.cube:nth-of-type(4) {
  -webkit-animation-delay: -9s;
          animation-delay: -9s;
}
@-webkit-keyframes move {
  0%,
    87.5%,
    100% {
    -webkit-transform: translate(1em, 0em);
            transform: translate(1em, 0em);
  }
  12.5% {
    -webkit-transform: translate(2em, 0em);
            transform: translate(2em, 0em);
  }
  25% {
    -webkit-transform: translate(2em, 1em);
            transform: translate(2em, 1em);
  }
  37.5%, 
    50% {
    -webkit-transform: translate(1em, 1em);
            transform: translate(1em, 1em);
  }
  62.5% {
    -webkit-transform: translate(0em, 1em);
            transform: translate(0em, 1em);
  }
  75% {
    -webkit-transform: translate(0em, 0em);
            transform: translate(0em, 0em);
  }
}
@keyframes move {
  0%,
    87.5%,
    100% {
    -webkit-transform: translate(1em, 0em);
            transform: translate(1em, 0em);
  }
  12.5% {
    -webkit-transform: translate(2em, 0em);
            transform: translate(2em, 0em);
  }
  25% {
    -webkit-transform: translate(2em, 1em);
            transform: translate(2em, 1em);
  }
  37.5%, 
    50% {
    -webkit-transform: translate(1em, 1em);
            transform: translate(1em, 1em);
  }
  62.5% {
    -webkit-transform: translate(0em, 1em);
            transform: translate(0em, 1em);
  }
  75% {
    -webkit-transform: translate(0em, 0em);
            transform: translate(0em, 0em);
  }
}
.box {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  width: 3em;
  height: 2em;
  margin: 30vmin auto;
  font-size: 50px;
  -webkit-transform-style: preserve-3d;
          transform-style: preserve-3d;
  -webkit-transform: rotateX(60deg) rotateZ(45deg);
          transform: rotateX(60deg) rotateZ(45deg);
}
.box:hover * {
  -webkit-animation-play-state: paused;
          animation-play-state: paused;
}
.box:active * {
  -webkit-animation-play-state: running;
          animation-play-state: running;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  height: 100%;
}

body {
  display: -webkit-box;
  display: -ms-flexbox;
  display: flex;
  -webkit-box-orient: vertical;
  -webkit-box-direction: normal;
      -ms-flex-direction: column;
          flex-direction: column;
  min-height: 100%;
  margin: 0;
  line-height: 1.4;
}

.intro {
  width: 90%;
  max-width: 50rem;
  padding-top: .5em;
  padding-bottom: 1rem;
  margin: 0 auto 1em;
  font-size: calc(1rem + 2vmin);
  text-transform: capitalize;
  text-align: center;
  font-family: serif;
  border-bottom: 1px dashed rgba(0, 0, 0, 0.5);
}

.info {
  margin: auto 0 0;
  padding: 1em;
  font-size: .9em;
  font-style: italic;
  font-family: serif;
  text-align: right;
  opacity: .5;
}
.info a {
  color: inherit;
}

Готовый пример:

See the Pen [CSS Animation] PCPP Loading Boxes by Denis (@deniscreative) on CodePen.