import Document, { Head, Main, NextScript } from 'next/document' import { flush } from '../styletron' export default class MyDocument extends Document { static getInitialProps ({ renderPage }) { const page = renderPage() const styletron = flush() const stylesheets = styletron ? styletron.getStylesheets() : [] return { ...page, stylesheets } } render () { return ( My page {this.props.stylesheets.map((sheet, i) => (