css loading动画

以下是两个使用CSS实现的loading动画：

1. 经典款loading动画，只需一个div元素即可完成：

.loader-6 {
  width: 48px;
  height: 48px;
  border: 2px solid #FFF;
  border-radius: 50%;
  display: inline-block;
  position: relative;
  -webkit-animation: rotation 1s linear infinite;
  animation: rotation 1s linear infinite;
}

.loader-6:after {
  content: "";
  position: absolute;
  left: 50%;
  top: 0;
  background: #FF3D00;
  width: 3px;
  height: 24px;
  transform: translateX(-50%);
}

@-webkit-keyframes rotation {
  from {
    -webkit-transform: rotate(0deg);
    transform: rotate(0deg);
  }
  to {
    -webkit-transform: rotate(359deg);
    transform: rotate(359deg);
  }
}

@keyframes rotation {
  from {
    -webkit-transform: rotate(0deg);
    transform: rotate(0deg);
  }
  to {
    -webkit-transform: rotate(359deg);
    transform: rotate(359deg);
  }
}

2. loader-7动画，使用多个div元素实现：

.loader-7 {
  width: 40px;
  height: 40px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.loader-7 div {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background-color: #FF3D00;
  animation: loader-7 1s ease-in-out infinite;
}

.loader-7 div:nth-child(1) {
  animation-delay: 0s;
}

.loader-7 div:nth-child(2) {
  animation-delay: 0.1s;
}

.loader-7 div:nth-child(3) {
  animation-delay: 0.2s;
}

.loader-7 div:nth-child(4) {
  animation-delay: 0.3s;
}

.loader-7 div:nth-child(5) {
  animation-delay: 0.4s;
}

.loader-7 div:nth-child(6) {
  animation-delay: 0.5s;
}

.loader-7 div:nth-child(7) {
  animation-delay: 0.6s;
}

.loader-7 div:nth-child(8) {
  animation-delay: 0.7s;
}

@keyframes loader-7 {
  0% {
    transform: scale(1);
  }
  20% {
    transform: scale(1, 2.5);
  }
  40% {
    transform: scale(1);
  }
}