map-tool/public/assets/esri/themes/base/widgets/_Spinner.scss

$spinner_size: 24px;

@mixin spinner() {
  .esri-ui {
    .esri-spinner {
      display: none;
      position: absolute;
      top: -999em;
      left: -999em;
      transform-origin: 0 0;
      opacity: 0;
      z-index: 2;
      box-shadow: none;
      background-color: transparent;
      padding: 0;
      width: $spinner_size;
      height: $spinner_size;
      overflow: visible;
      pointer-events: none;
    }

    .esri-spinner::before {
      display: block;
      position: absolute;
      margin: -50% 0 0 -50%;
      background: url("../base/images/Loading_Indicator_double_32.svg") no-repeat center;
      width: 100%;
      height: 100%;
      animation: esri-spinner--rotate-animation 750ms linear infinite;
      content: "";
    }

    .esri-spinner--start {
      display: block;
      animation: esri-spinner--start-animation 250ms cubic-bezier(0.17, 0.67, 0.36, 0.99) forwards;
    }

    .esri-spinner--finish {
      display: block;
      opacity: 1;
      animation: esri-spinner--finish-animation 125ms ease-in forwards;
      animation-delay: 75ms;
    }
  }
}

@keyframes esri-spinner--start-animation {
  0% {
    transform: scale(0);
    opacity: 0;
  }

  100% {
    transform: scale(1);
    opacity: 1;
  }
}

@keyframes esri-spinner--finish-animation {
  0% {
    transform: scale(1);
    opacity: 1;
  }

  100% {
    transform: scale(0);
    opacity: 0;
  }
}

@keyframes esri-spinner--rotate-animation {
  0% {
    transform: rotate(0deg);
  }

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

@if $include_Spinner == true {
  @include spinner();
}