code: function () {
          var data = this.data;
          var targetEl = this.data.target;
  
          // Only set up once.
          if (targetEl.dataset.setImageFadeSetup) { return; }
          targetEl.dataset.setImageFadeSetup = true;
  
          // Create animation.
          targetEl.setAttribute('animation__fade', {
              property: 'material.color',
              startEvents: 'set-image-fade',
              dir: 'alternate',
              dur: data.dur,
              from: '#FFF',
              to: '#000'
          });
      }
docs: Setup fade-in + fade-out.