.loading {
  width: 200px;
  height: 200px;
  box-sizing: border-box;
  border-radius: 50%;
  border-top: 10px solid #e74c3c;
  position: relative;
  animation: a1 2s linear infinite;
}

.loading::before, .loading::after {
  content: '';
  width: 200px;
  height: 200px;
  position: absolute;
  left: 0;
  top: -10px;
  box-sizing: border-box;
  border-radius: 50%;
}

.loading::before {
  border-top: 10px solid #e67e22;
  transform: rotate(120deg);
}

.loading::after {
  border-top: 10px solid #3498db;
  transform: rotate(240deg);
}

.loading span {
  position: absolute;
  width: 200px;
  height: 200px;
  color: #fff;
  text-align: center;
  line-height: 200px;
  animation: a2 2s linear infinite;
}