Export distinct css for themes

[AdaltonLeite]

I have two themes ( Light and Dark) for my website, how do I export distinct css to each one?

For example:

/static/css/dark.css
/static/css/light.css

next.config.js

module.exports = withSass({
	cssModules: true,  
	cssLoaderOptions: {
		importLoaders: 1,
		localIdentName: '[local]___[hash:base64:5]',
		root: '/',
		url: false,
		includePaths: ['templates/dark', 'templates/style']
	},
	distDir: 'build',
});```