postcss-nested VS svelte-preprocess

And we have to make sure that it runs before the nesting plugin, otherwise it will not work at all due to an issue when using both plugins together.

postcss-nested

What you're describing is nesting, which is currently in the proposal stages for CSS. That being said, nesting has long been a feature in many preprocessors, such as sass and less. You can also use this PostCSS plugin if you only want the nesting and nothing else.

My PostCSS Config contains postcss-preset-env already which should support for CSS nesting. I also installed postcss-nested & postcss-css-variables, just in case.

PostCSS Nested - so I can use Sass-like nesting.

A quick example that demonstrates what I've said would be the postcss nesting plugin: https://github.com/postcss/postcss-nested

You can learn more about the official svelte-preprocess and other available config here

svelte-preprocess is responsible for processing things like TypeScript and SCSS. The svelte compiler itself is only responsible for turning the svelte file into JavaScript.

svelte-preprocess should handle scss out-of-the-box, and it’s included in SvelteKit by default if you created your project with create-svelte

// svelte.config.js import sveltePreprocess from 'svelte-preprocess' export default { // Consult https://github.com/sveltejs/svelte-preprocess // for more information about preprocessors // **here -> postcss: true** preprocess: sveltePreprocess({ postcss: true, }) }

/** @type {import('@sveltejs/kit').Config} */ const config = { // Consult https://github.com/sveltejs/svelte-preprocess // for more information about preprocessors preprocess: preprocess({ typescript: true, postcss: true, scss: { prependData: @import 'src/styles/helpers/functions.scss'; } }), kit: { paths: { assets: '', base: dev ? '' : '/route/in/website' }, trailingSlash: 'always', adapter: adapter({ pages: 'build', assets: 'build', fallback: 'index.html' }), files: { hooks: 'src/hooks', }, prerender: { default: true, }, } };

Continue to use tags

In svelte.config.js ... (import aliases can be whatever you want)

1. import svelte_preprocess from 'svelte-preprocess'
2. import autoprefixer from 'autoprefixer'
3. pass the Svelte preprocessor to Kit's preprocess config option and pass the postcss plugin to that Svelte preprocessor:

svelte.config.js

import svelte_proprocess from 'svelte-process'
import autoprefixer from 'autoprefixer'

const config = {
    // Consult https://github.com/sveltejs/svelte-preprocess for more info
    preprocess: [
        svelte_preprocess({
            postcss: {
                plugins: [autoprefixer()]
            }
        })
    ]
}

import adapter from '@sveltejs/adapter-auto'; import preprocess from 'svelte-preprocess'; import { mdsvex } from 'mdsvex'; import remarkMath from 'remark-math'; import rehypeKatex from 'rehype-katex-svelte'; /** @type {import('@sveltejs/kit').Config} */ const config = { extensions: ['.svelte', '.svx', '.md'], // Consult https://github.com/sveltejs/svelte-preprocess // for more information about preprocessors preprocess: [ preprocess(), mdsvex({ extensions: ['.svx', '.md'], smartypants: true, layout: { project: "./src/routes/projects/layout.svelte", post: "./src/routes/blog/layout.svelte", }, remarkPlugins: [remarkMath], rehypePlugins: [rehypeKatex], }), ], kit: { adapter: adapter({ edge: false, external: [], split: false }) } }; export default config;

Have you tried https://github.com/sveltejs/svelte-preprocess

// We have changed the adapter line to use adapter-node@next import adapter from '@sveltejs/adapter-node@next'; import preprocess from 'svelte-preprocess'; /** @type {import('@sveltejs/kit').Config} */ const config = { // Consult https://github.com/sveltejs/svelte-preprocess // for more information about preprocessors preprocess: preprocess(), kit: { // We have changed this to point to a build directory adapter: adapter({ out: 'build' }) } }; export default config;