async _hideAnimation({ contentNode }) {
    if (this._contentHeight === '0px') {
      return;
    }
    ['opacity', 'padding', 'max-height'].map(prop => contentNode.style.setProperty(prop, '0'));
    await this._waitForTransition({ contentNode });
  }
Trigger hide animation and wait for transition to be finished.
@param {Object} options - element node and its options
@param {HTMLElement} options.contentNode
@override