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<dom-module id=“paper-spinner-styles”>

<template>
  <style>
    /*
    /**************************/
    /* STYLES FOR THE SPINNER */
    /**************************/

    /*
     * Constants:
     *      ARCSIZE     = 270 degrees (amount of circle the arc takes up)
     *      ARCTIME     = 1333ms (time it takes to expand and contract arc)
     *      ARCSTARTROT = 216 degrees (how much the start location of the arc
     *                                should rotate each time, 216 gives us a
     *                                5 pointed star shape (it's 360/5 * 3).
     *                                For a 7 pointed star, we might do
     *                                360/7 * 3 = 154.286)
     *      SHRINK_TIME = 400ms
     */

    :host {
      display: inline-block;
      position: relative;
      width: 28px;
      height: 28px;

      /* 360 * ARCTIME / (ARCSTARTROT + (360-ARCSIZE)) */
      --paper-spinner-container-rotation-duration: 1568ms;

      /* ARCTIME */
      --paper-spinner-expand-contract-duration: 1333ms;

      /* 4 * ARCTIME */
      --paper-spinner-full-cycle-duration: 5332ms;

      /* SHRINK_TIME */
      --paper-spinner-cooldown-duration: 400ms;
    }

    #spinnerContainer {
      width: 100%;
      height: 100%;

      /* The spinner does not have any contents that would have to be
       * flipped if the direction changes. Always use ltr so that the
       * style works out correctly in both cases. */
      direction: ltr;
    }

    #spinnerContainer.active {
      -webkit-animation: container-rotate var(--paper-spinner-container-rotation-duration) linear infinite;
      animation: container-rotate var(--paper-spinner-container-rotation-duration) linear infinite;
    }

    @-webkit-keyframes container-rotate {
      to { -webkit-transform: rotate(360deg) }
    }

    @keyframes container-rotate {
      to { transform: rotate(360deg) }
    }

    .spinner-layer {
      position: absolute;
      width: 100%;
      height: 100%;
      opacity: 0;
      white-space: nowrap;
      border-color: var(--paper-spinner-color, --google-blue-500);
    }

    .layer-1 {
      border-color: var(--paper-spinner-layer-1-color, --google-blue-500);
    }

    .layer-2 {
      border-color: var(--paper-spinner-layer-2-color, --google-red-500);
    }

    .layer-3 {
      border-color: var(--paper-spinner-layer-3-color, --google-yellow-500);
    }

    .layer-4 {
      border-color: var(--paper-spinner-layer-4-color, --google-green-500);
    }

    /**
     * IMPORTANT NOTE ABOUT CSS ANIMATION PROPERTIES (keanulee):
     *
     * iOS Safari (tested on iOS 8.1) does not handle animation-delay very well - it doesn't
     * guarantee that the animation will start _exactly_ after that value. So we avoid using
     * animation-delay and instead set custom keyframes for each color (as layer-2undant as it
     * seems).
     */
    .active .spinner-layer {
      -webkit-animation-name: fill-unfill-rotate;
      -webkit-animation-duration: var(--paper-spinner-full-cycle-duration);
      -webkit-animation-timing-function: cubic-bezier(0.4, 0.0, 0.2, 1);
      -webkit-animation-iteration-count: infinite;
      animation-name: fill-unfill-rotate;
      animation-duration: var(--paper-spinner-full-cycle-duration);
      animation-timing-function: cubic-bezier(0.4, 0.0, 0.2, 1);
      animation-iteration-count: infinite;
      opacity: 1;
    }

    .active .spinner-layer.layer-1 {
      -webkit-animation-name: fill-unfill-rotate, layer-1-fade-in-out;
      animation-name: fill-unfill-rotate, layer-1-fade-in-out;
    }

    .active .spinner-layer.layer-2 {
      -webkit-animation-name: fill-unfill-rotate, layer-2-fade-in-out;
      animation-name: fill-unfill-rotate, layer-2-fade-in-out;
    }

    .active .spinner-layer.layer-3 {
      -webkit-animation-name: fill-unfill-rotate, layer-3-fade-in-out;
      animation-name: fill-unfill-rotate, layer-3-fade-in-out;
    }

    .active .spinner-layer.layer-4 {
      -webkit-animation-name: fill-unfill-rotate, layer-4-fade-in-out;
      animation-name: fill-unfill-rotate, layer-4-fade-in-out;
    }

    @-webkit-keyframes fill-unfill-rotate {
      12.5% { -webkit-transform: rotate(135deg) } /* 0.5 * ARCSIZE */
      25%   { -webkit-transform: rotate(270deg) } /* 1   * ARCSIZE */
      37.5% { -webkit-transform: rotate(405deg) } /* 1.5 * ARCSIZE */
      50%   { -webkit-transform: rotate(540deg) } /* 2   * ARCSIZE */
      62.5% { -webkit-transform: rotate(675deg) } /* 2.5 * ARCSIZE */
      75%   { -webkit-transform: rotate(810deg) } /* 3   * ARCSIZE */
      87.5% { -webkit-transform: rotate(945deg) } /* 3.5 * ARCSIZE */
      to    { -webkit-transform: rotate(1080deg) } /* 4   * ARCSIZE */
    }

    @keyframes fill-unfill-rotate {
      12.5% { transform: rotate(135deg) } /* 0.5 * ARCSIZE */
      25%   { transform: rotate(270deg) } /* 1   * ARCSIZE */
      37.5% { transform: rotate(405deg) } /* 1.5 * ARCSIZE */
      50%   { transform: rotate(540deg) } /* 2   * ARCSIZE */
      62.5% { transform: rotate(675deg) } /* 2.5 * ARCSIZE */
      75%   { transform: rotate(810deg) } /* 3   * ARCSIZE */
      87.5% { transform: rotate(945deg) } /* 3.5 * ARCSIZE */
      to    { transform: rotate(1080deg) } /* 4   * ARCSIZE */
    }

    @-webkit-keyframes layer-1-fade-in-out {
      0% { opacity: 1 }
      25% { opacity: 1 }
      26% { opacity: 0 }
      89% { opacity: 0 }
      90% { opacity: 1 }
      to { opacity: 1 }
    }

    @keyframes layer-1-fade-in-out {
      0% { opacity: 1 }
      25% { opacity: 1 }
      26% { opacity: 0 }
      89% { opacity: 0 }
      90% { opacity: 1 }
      to { opacity: 1 }
    }

    @-webkit-keyframes layer-2-fade-in-out {
      0% { opacity: 0 }
      15% { opacity: 0 }
      25% { opacity: 1 }
      50% { opacity: 1 }
      51% { opacity: 0 }
      to { opacity: 0 }
    }

    @keyframes layer-2-fade-in-out {
      0% { opacity: 0 }
      15% { opacity: 0 }
      25% { opacity: 1 }
      50% { opacity: 1 }
      51% { opacity: 0 }
      to { opacity: 0 }
    }

    @-webkit-keyframes layer-3-fade-in-out {
      0% { opacity: 0 }
      40% { opacity: 0 }
      50% { opacity: 1 }
      75% { opacity: 1 }
      76% { opacity: 0 }
      to { opacity: 0 }
    }

    @keyframes layer-3-fade-in-out {
      0% { opacity: 0 }
      40% { opacity: 0 }
      50% { opacity: 1 }
      75% { opacity: 1 }
      76% { opacity: 0 }
      to { opacity: 0 }
    }

    @-webkit-keyframes layer-4-fade-in-out {
      0% { opacity: 0 }
      65% { opacity: 0 }
      75% { opacity: 1 }
      90% { opacity: 1 }
      to { opacity: 0 }
    }

    @keyframes layer-4-fade-in-out {
      0% { opacity: 0 }
      65% { opacity: 0 }
      75% { opacity: 1 }
      90% { opacity: 1 }
      to { opacity: 0 }
    }

    .circle-clipper {
      display: inline-block;
      position: relative;
      width: 50%;
      height: 100%;
      overflow: hidden;
      border-color: inherit;
    }

    /**
     * Patch the gap that appear between the two adjacent div.circle-clipper while the
     * spinner is rotating (appears on Chrome 50, Safari 9.1.1, and Edge).
     */
    .spinner-layer::after {
      left: 45%;
      width: 10%;
      border-top-style: solid;
    }

    .spinner-layer::after,
    .circle-clipper::after {
      content: '';
      box-sizing: border-box;
      position: absolute;
      top: 0;
      border-width: var(--paper-spinner-stroke-width, 3px);
      border-color: inherit;
      border-radius: 50%;
    }

    .circle-clipper::after {
      bottom: 0;
      width: 200%;
      border-style: solid;
      border-bottom-color: transparent !important;
    }

    .circle-clipper.left::after {
      left: 0;
      border-right-color: transparent !important;
      -webkit-transform: rotate(129deg);
      transform: rotate(129deg);
    }

    .circle-clipper.right::after {
      left: -100%;
      border-left-color: transparent !important;
      -webkit-transform: rotate(-129deg);
      transform: rotate(-129deg);
    }

    .active .gap-patch::after,
    .active .circle-clipper::after {
      -webkit-animation-duration: var(--paper-spinner-expand-contract-duration);
      -webkit-animation-timing-function: cubic-bezier(0.4, 0.0, 0.2, 1);
      -webkit-animation-iteration-count: infinite;
      animation-duration: var(--paper-spinner-expand-contract-duration);
      animation-timing-function: cubic-bezier(0.4, 0.0, 0.2, 1);
      animation-iteration-count: infinite;
    }

    .active .circle-clipper.left::after {
      -webkit-animation-name: left-spin;
      animation-name: left-spin;
    }

    .active .circle-clipper.right::after {
      -webkit-animation-name: right-spin;
      animation-name: right-spin;
    }

    @-webkit-keyframes left-spin {
      0% { -webkit-transform: rotate(130deg) }
      50% { -webkit-transform: rotate(-5deg) }
      to { -webkit-transform: rotate(130deg) }
    }

    @keyframes left-spin {
      0% { transform: rotate(130deg) }
      50% { transform: rotate(-5deg) }
      to { transform: rotate(130deg) }
    }

    @-webkit-keyframes right-spin {
      0% { -webkit-transform: rotate(-130deg) }
      50% { -webkit-transform: rotate(5deg) }
      to { -webkit-transform: rotate(-130deg) }
    }

    @keyframes right-spin {
      0% { transform: rotate(-130deg) }
      50% { transform: rotate(5deg) }
      to { transform: rotate(-130deg) }
    }

    #spinnerContainer.cooldown {
      -webkit-animation: container-rotate var(--paper-spinner-container-rotation-duration) linear infinite, fade-out var(--paper-spinner-cooldown-duration) cubic-bezier(0.4, 0.0, 0.2, 1);
      animation: container-rotate var(--paper-spinner-container-rotation-duration) linear infinite, fade-out var(--paper-spinner-cooldown-duration) cubic-bezier(0.4, 0.0, 0.2, 1);
    }

    @-webkit-keyframes fade-out {
      0% { opacity: 1 }
      to { opacity: 0 }
    }

    @keyframes fade-out {
      0% { opacity: 1 }
      to { opacity: 0 }
    }
  </style>
</template>

</dom-module>