npm install tailwindcss-debug-screens --save-dev //in tailwind.config.ts module.exports = { //... plugins: [ require('tailwindcss-debug-screens'), ] } //at root of project layout.tsx in nextjs <html lang="en"> <body className={cn( sansSerifBookFLF.variable, workSans.variable, process.env.NODE_ENV === 'development' && 'debug-screens', )} > <Toaster /> {children} </body> </html>