CSS loaders with gradient

loader_1.css

.loader {
  background: linear-gradient(to right, #2f54eb 10%, rgba(255, 255, 255, 0) 80%);
  /* Show only 10px from the border */
  
  -webkit-mask:radial-gradient(farthest-side,transparent calc(100% - 10px),#fff 0);
  
  width: 150px;
  height: 150px;
  border-radius: 50%;  
  position: fixed;
  top: calc(50% - 50px);
  left: calc(50% - 50px);  
  animation: rotate 1s linear infinite; 
}

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

loader_2.css

.loader {
  font-size: 20px;
  margin: 50px auto;
  text-indent: -9999em;
  width: 11em;
  height: 11em;
  border-radius: 50%;
  background: #2f54eb;
  background: -moz-linear-gradient(left, #2f54eb 10%, rgba(255, 255, 255, 0) 42%);
  background: -webkit-linear-gradient(left, #2f54eb 10%, rgba(255, 255, 255, 0) 42%);
  background: -o-linear-gradient(left, #2f54eb 10%, rgba(255, 255, 255, 0) 42%);
  background: -ms-linear-gradient(left, #2f54eb 10%, rgba(255, 255, 255, 0) 42%);
  background: linear-gradient(to right, #2f54eb 10%, rgba(255, 255, 255, 0) 42%);
  -webkit-mask:radial-gradient(farthest-side,transparent calc(100% - 10px),#fff 0);
  position: relative;
  -webkit-animation: load3 1.4s infinite linear;
  animation: load3 1.4s infinite linear;
  -webkit-transform: translateZ(0);
  -ms-transform: translateZ(0);
  transform: translateZ(0);
}
.loader:before {
  width: 50%;
  height: 50%;
  background: #2f54eb;
  border-radius: 100% 0 0 0;
  position: absolute;
  top: 0;
  left: 0;
  content: '';
}
.loader:after {
  background: #fff;
  width: 90%;
  height: 90%;
  border-radius: 50%;
  content: '';
  margin: auto;
  position: absolute;
  top: 0;
  left: 0;
  bottom: 0;
  right: 0;
}
@-webkit-keyframes load3 {
  0% {
    -webkit-transform: rotate(0deg);
    transform: rotate(0deg);
  }
  100% {
    -webkit-transform: rotate(360deg);
    transform: rotate(360deg);
  }
}
@keyframes load3 {
  0% {
    -webkit-transform: rotate(0deg);
    transform: rotate(0deg);
  }
  100% {
    -webkit-transform: rotate(360deg);
    transform: rotate(360deg);
  }
}