.loader {
  margin-left: 4px;
  display: inline-block;
  height: 8px;
  width: 17%;
  position: relative;
  overflow: hidden;
  background-color: transparent;
  border-radius: 1px;
}
.loader:before{
  display: inline-block;
  position: absolute;
  content: "";
  left: -200px;
  width: 50px;
  height: 6px;
  background-color: #29b951;
  border: 1px solid #cee812;
  animation: loading 5s linear infinite;
  border-radius: 1px;
}

@keyframes loading {
    from {left: -200px; width: 30%;}
    50% {width: 30%;}
    70% {width: 70%;}
    80% { left: 50%;}
    95% {left: 120%;}
    to {left: 100%;}
}