message: this.container.current fix
diff: @@ -280,7 +280,8 @@ export default class Gallery extends Component {
  this.initializeSlides();
  const { layerWidth, slides } = this.state;
  - const containerWidth = this.container.offsetWidth;
  + const containerWidth = this.container.current.offsetWidth;
  +
  const viewportWidth = this.viewport.offsetWidth;
  this.setState({
  