pages/_document.js

import Document, { Head, Html, Main, NextScript } from 'next/document';
import Script from 'next/script';
import { ServerStyleSheet } from 'styled-components';

export default class MyDocument extends Document {
  static async getInitialProps(ctx) {
    const sheet = new ServerStyleSheet();
    const originalRenderPage = ctx.renderPage;
    try {
      ctx.renderPage = () =>
        originalRenderPage({
          enhanceApp: (App) => (props) => sheet.collectStyles(<App {...props} />)
        });

      const initialProps = await Document.getInitialProps(ctx);
      return {
        ...initialProps,
        styles: (
          <>
            {initialProps.styles}
            {sheet.getStyleElement()}
          </>
        )
      };
    } finally {
      sheet.seal();
    }
  }

  render() {
    // Polyfill Intl API for older browsers
    const polyfill = `https://cdn.polyfill.io/v3/polyfill.min.js?features=Intl.~locale.${this.props.locale}`;

    return (
      <Html>
        <Head />
        <body>
          <Main />
          <Script src={polyfill} />
          <Script
            id="locale-data"
            dangerouslySetInnerHTML={{
              __html: this.props.localeDataScript
            }}
          />
          <NextScript />
        </body>
      </Html>
    );
  }
}