Edit in JSFiddle

  <div class="demo progress-outer">
    <div class="progress-inner">
      <div class="progress-bg"></div>
    </div>
  </div>

.demo{
  margin-top:40px auto;
  width:200px;
  height:12px;
}
.progress-outer{
  border-radius: 8px;
  overflow: hidden;
  /* position: relative; */
}
.progress-inner{
  width:inherit;
  height:inherit;
  background: rgba(180, 160, 120, .5);
}
.progress-bg{
  width:60%;
  height:inherit;
  border-radius: 6px;
  background:repeating-linear-gradient(-45deg, #D9CFBB  25%, #C3B393 0, #C3B393 50%,#D9CFBB 0, #D9CFBB 75%, #C3B393 0);
  background-size:16px 16px;
  animation:dong 20s linear infinite;
}
@keyframes dong{
  to {
    background-position: 200% 0;
  }
}