app/layout.tsx export default function RootLayout({
  // Layouts must accept a children prop.
  // This will be populated with nested layouts or pages
  children,
}: {
  children: React.ReactNode
}) {
  return (
    <html lang="en">
      <body>{children}</body>
    </html>
  )
}
The app directory must include a root layout.
The root layout must define <html>, and <body> tags since Next.js does not automatically create them
The root layout replaces the pages/_app.tsx and pages/_document.tsx files.
.js, .jsx, or .tsx extensions can be used for layout files.
To manage <head> HTML elements, you can use the built-in SEO support:
app/layout.tsx import { Metadata } from 'next'
 
export const metadata: Metadata = {
  title: 'Home',