使用 CSS3 实现超炫的 Loading（加载）动画效果

.spinner {

  margin: 100px auto;

  width: 20px;

  height: 20px;

  position: relative;

}

.container1 > div, .container2 > div, .container3 > div {

  width: 6px;

  height: 6px;

  background-color: #333;

  border-radius: 100%;

  position: absolute;

  -webkit-animation: bouncedelay 1.2s infinite ease-in-out;

  animation: bouncedelay 1.2s infinite ease-in-out;

  -webkit-animation-fill-mode: both;

  animation-fill-mode: both;

}

.spinner .spinner-container {

  position: absolute;

  width: 100%;

  height: 100%;

}

.container2 {

  -webkit-transform: rotateZ(45deg);

  transform: rotateZ(45deg);

}

.container3 {

  -webkit-transform: rotateZ(90deg);

  transform: rotateZ(90deg);

}

.circle1 { top: 0; left: 0; }

.circle2 { top: 0; right: 0; }

.circle3 { right: 0; bottom: 0; }

.circle4 { left: 0; bottom: 0; }

.container2 .circle1 {

  -webkit-animation-delay: -1.1s;

  animation-delay: -1.1s;

}

.container3 .circle1 {

  -webkit-animation-delay: -1.0s;

  animation-delay: -1.0s;

}

.container1 .circle2 {

  -webkit-animation-delay: -0.9s;

  animation-delay: -0.9s;

}

.container2 .circle2 {

  -webkit-animation-delay: -0.8s;

  animation-delay: -0.8s;

}

.container3 .circle2 {

  -webkit-animation-delay: -0.7s;

  animation-delay: -0.7s;

}

.container1 .circle3 {

  -webkit-animation-delay: -0.6s;

  animation-delay: -0.6s;

}

.container2 .circle3 {

  -webkit-animation-delay: -0.5s;

  animation-delay: -0.5s;

}

.container3 .circle3 {

  -webkit-animation-delay: -0.4s;

  animation-delay: -0.4s;

}

.container1 .circle4 {

  -webkit-animation-delay: -0.3s;

  animation-delay: -0.3s;

}

.container2 .circle4 {

  -webkit-animation-delay: -0.2s;

  animation-delay: -0.2s;

}

.container3 .circle4 {

  -webkit-animation-delay: -0.1s;

  animation-delay: -0.1s;

}

@-webkit-keyframes bouncedelay {

  0%, 80%, 100% { -webkit-transform: scale(0.0) }

  40% { -webkit-transform: scale(1.0) }

}

@keyframes bouncedelay {

  0%, 80%, 100% {

    transform: scale(0.0);

    -webkit-transform: scale(0.0);

  } 40% {

    transform: scale(1.0);

    -webkit-transform: scale(1.0);

  }

}