.loader{
    display: none;
    position: fixed;
    top:0;
    left:0;
    height: 3px;
    width: 100%;
    border: 0px solid #000;
    border-radius: 1px;
    overflow: hidden;
    z-index: 20;
  }
  .loader__show {
    display: block;
  }
  .loader::after {
    content: '';
    width: 20%;
    height: 100%;
    background: #FF3D00;
    position: absolute;
    top: 0;
    left: 0;
    box-sizing: border-box;
    animation: animloader 2s linear infinite;
  }
  
  @keyframes animloader {
    0% {
      left: 0;
      transform: translateX(-100%);
    }
    100% {
      left: 100%;
      transform: translateX(0%);
    }
  }