docs: function (key, styles) {
      key = camelToKebab(key)
      let stylesText = ''
      for (const k in styles) {
        if (styles.hasOwnProperty(k)) {
          stylesText += camelToKebab(k) + ':' + styles[k] + ';'
        }
      }
      const styleText = `@${key}{${stylesText}}`
      appendCss(styleText, 'dom-added-rules')
    }