gitlab-org--gitlab-foss/app/assets/stylesheets/framework/logo.scss

@mixin unique-keyframes {
  $animation-name: unique-id();
  @include webkit-prefix(animation-name, $animation-name);

  @-webkit-keyframes #{$animation-name} {
    @content;
  }
  @keyframes #{$animation-name} {
    @content;
  }
}

@mixin tanuki-logo-colors($path-color) {
  fill: $path-color;
  transition: all 0.8s;

  &:hover {
    fill: lighten($path-color, 25%);
    transition: all 0.1s;
  }
}

@mixin tanuki-second-highlight-animations($tanuki-color) {
  @include unique-keyframes {
    10%, 80% {
      fill: #{$tanuki-color}
    }
    20%, 90% {
      fill: lighten($tanuki-color, 25%);
    }
  }
}

@mixin tanuki-forth-highlight-animations($tanuki-color) {
  @include unique-keyframes {
    30%, 60% {
      fill: #{$tanuki-color};
    }
    40%, 70% {
      fill: lighten($tanuki-color, 25%);
    }
  }
}

.tanuki-logo {

  .tanuki-left-ear,
  .tanuki-right-ear,
  .tanuki-nose {
    @include tanuki-logo-colors($tanuki-red);
  }

  .tanuki-left-eye,
  .tanuki-right-eye {
    @include tanuki-logo-colors($tanuki-orange);
  }

  .tanuki-left-cheek,
  .tanuki-right-cheek {
    @include tanuki-logo-colors($tanuki-yellow);
  }

  &.animate {
    .tanuki-shape {
      @include webkit-prefix(animation-duration, 1.5s);
      @include webkit-prefix(animation-iteration-count, infinite);
    }

    .tanuki-left-cheek {
      @include unique-keyframes {
        0%, 10%, 100% {
          fill: lighten($tanuki-yellow, 25%);
        }
        90% {
          fill: $tanuki-yellow;
        }
      }
    }

    .tanuki-left-eye {
      @include tanuki-second-highlight-animations($tanuki-orange);
    }

    .tanuki-left-ear {
      @include tanuki-second-highlight-animations($tanuki-red);
    }

    .tanuki-nose {
      @include unique-keyframes {
        20%, 70% {
          fill: $tanuki-red;
        }
        30%, 80% {
          fill: lighten($tanuki-red, 25%);
        }
      }
    }

    .tanuki-right-eye {
      @include tanuki-forth-highlight-animations($tanuki-orange);
    }

    .tanuki-right-ear {
      @include tanuki-forth-highlight-animations($tanuki-red);
    }

    .tanuki-right-cheek {
      @include unique-keyframes {
        40% {
          fill: $tanuki-yellow;
        }
        60% {
          fill: lighten($tanuki-yellow, 25%);
        }
      }
    }
  }
}