code: function insertCss(styles, { replace = false, prepend = false, prefix = 's' } = {}) {
    const ids = []
    for (let i = 0; i < styles.length; i++) {
      const [moduleId, css, media, sourceMap] = styles[i]
      const id = `${prefix}${moduleId}-${i}`
  
      ids.push(id)
  
      if (inserted[id]) {
        if (!replace) {
          inserted[id]++
          continue
        }
      }
  
      inserted[id] = 1
  
      let elem = document.getElementById(id)
      let create = false
  
      if (!elem) {
        create = true
  
        elem = document.createElement('style')
        elem.setAttribute('type', 'text/css')
        elem.id = id
  
        if (media) {
          elem.setAttribute('media', media)
        }
      }
  
      let cssText = css
      if (sourceMap && typeof btoa === 'function') {
        // skip IE9 and below, see http://caniuse.com/atob-btoa
        cssText += `\n/*# sourceMappingURL=data:application/json;base64,${b64EncodeUnicode(
          JSON.stringify(sourceMap),
        )}*/`
        cssText += `\n/*# sourceURL=${sourceMap.file}?${id}*/`
      }
  
      if ('textContent' in elem) {
        elem.textContent = cssText
      } else {
        elem.styleSheet.cssText = cssText
      }
  
      if (create) {
        if (prepend) {
          document.head.insertBefore(elem, document.head.childNodes[0])
        } else {
          document.head.appendChild(elem)
        }
      }
    }
  
    return removeCss.bind(null, ids)
  }
docs: Example:
  // Insert CSS styles object generated by `css-loader` into DOM
  var removeCss = insertCss([[1, 'body { color: red; }']]);
  
  // Remove it from the DOM
  removeCss();