toStyle(item, renderer) {
    const cssString = this.generateView(
      item,
      `.element-item[data-id='${item.id}']`
    );
    return (
      /*html*/ `
<style type='text/css' data-renderer-type="html" data-id='${item.id}' data-timestamp='${item.timestamp}'>
${cssString}
</style>
    ` +
      item.layers
        .map((it) => {
          return renderer.toStyle(it, renderer);
        })
        .join("")
    );
  }
@param {Item} item
@param {HtmlRenderer} renderer