code: function scopeCssText (cssText, scope) {
    return transformCss(cssText, (rule) => {
      const transformed = {...rule}
      if (!rule.isScoped) {
        transformed.selector = scopeRule(rule, scope)
        transformed.isScoped = true
      }
      return transformed
    })
  }
docs: Transforms a CSS string to add a scoping selector to each rule
  @param {String} cssText
  @param {String} scope a unique identifier to use to scope the styles