PostCSS VS JSS

the plugins in the official PostCSS website were old like IE6 or the marquee tag, and

Hello internet. I just published a new blog post on how to implement dark mode with SvelteKit, optionally with PostCSS and TailwindCSS:

There are many frontend tools available for this purpose. For example, PostCSS is a popular CSS processor that can combine and minimize your code. With the right plugin, it can even fix your code for compatibility issues, making sure your CSS styles work for all browsers.

I use PostCSS to extend CSS’s features and to add a few things that make writing styles a little more convenient, but it could easily be swapped for another preprocessor like Sass or vanilla CSS. It’s up to you. You can view my PostCSS config here.

Code transpilation isn't specific to JavaScript, You can also add a level of transformation to your CSS source using tools like post-css. Most languages with a fairly mature ecosystem will probably have some tools to help with code transformation.

In large projects, it is still a good idea to use PostCSS, which will translate new CSS features to something that browsers understand today.

LiveCodes provides many of the commonly used developer tools. These include Monaco editor (that powers VS Code), Prettier, Emmet, Vim/Emacs modes, Babel, TypeScript, SCSS, Less, PostCSS, Jest and Testing Library, among others. All these tools run seamlessly in the browser without any installations or configurations. It feels like a very light-weight version of your own local development environment including the keyboard shortcuts, IntelliSense and code navigation features.

Usually, one of the first things I do on creating a new web app is to throw a UI library in to help style components. There are several UI libraries that can be used by Svelte, but in this case I went with daisyUI because it's a fairly popular UI library which includes tailwind. To install daisyUI, you first need to install tailwind. There's a few different ways to do this (such as this guide), but the easiest way I've found is the following command, which also adds PostCSS and AutoPrefixer:

Vanilla CSS has taken a similar path with ambitious working drafts, better browser support, and PostCSS to fill the gap for user agents lagging behind. So why is Sass/SCSS still so popular? Maybe we go so used to it that we might have forgotten what problems it was meant to solve in the first place.

Most websites those days are SPA applications that render on the front-side. There is also this trend of CSS in JavaScript also knowns as JSS that is debatable (makes everything overcomplicated), but in some specific cases, can be justified and very useful.

> why tf aren't we using JS for styling already

People are and have been for quite a while

https://cssinjs.org/

JSS

It is possible. At its most simple, you could just modify the style property on every element. That's not generally considered best practice, but there are a number of "CSS-in-JS" libraries which streamline the process. The typically generate dynamic CSS classes and apply them to your elements. A big one is JSS.

import React, { useState, useEffect } from "react"; import Amplify, { API, graphqlOperation } from "aws-amplify"; import { createBlog } from "./graphql/mutations"; import { listBlogs } from "./graphql/queries"; import awsExports from "./aws-exports"; import { ListBlogsQuery } from "./API"; Amplify.configure(awsExports); const initialState = { name: "", body: "" }; const App = () => { const [formState, setFormState] = useState(initialState); const [blogs, setBlogs] = useState(); useEffect(() => { fetchBlogs() }, []); const handleInputChange = (event: React.ChangeEvent) => { setFormState({ ...formState, [event.target.name]: event.target.value }); }; const fetchBlogs = async () => { try { const blogData = (await API.graphql(graphqlOperation(listBlogs))) as { data: ListBlogsQuery } setBlogs(blogData.data); } catch (err) { console.log("Error fetching blogs" + err); } }; const addBlog = async () => { try { if (!formState.name || !formState.body) return; const blog = { ...formState }; if (blogs) { await API.graphql(graphqlOperation(createBlog, { input: blog })); await fetchBlogs(); setFormState(initialState); } } catch (err) { console.log("error creating blog: ", err); } }; return (

Amplify Todos

Create Blog {blogs && blogs?.listBlogs?.items?.map((blog, index) => { return (

{blog?.name}

{blog?.body}

); })}

); }; const styles = { container: { width: 400, margin: "0 auto", display: "flex", //real weird issue: https://github.com/cssinjs/jss/issues/1344 flexDirection: "column" as "column", justifyContent: "center", padding: 20, }, todo: { marginBottom: 15 }, input: { border: "none", backgroundColor: "#ddd", marginBottom: 10, padding: 8, fontSize: 18, }, todoName: { fontSize: 20, fontWeight: "bold" }, todoDescription: { marginBottom: 0 }, button: { backgroundColor: "black", color: "white", outline: "none", fontSize: 18, padding: "12px 0px", }, }; export default App;

Material UI v5 brought some amazing updates, but switching from JSS to Emotion had an arguably nasty side-effect: it was no longer as straightforward to group your component styles in classes. Fortunately, a fantastic library emerged that allowed developers to not only reduce the extreme pain from migrating all their classes from v4's makeStyles to emotion, but to also to continue to writing classes in practically the same syntax, with wonderful TS type-safety. This library was tss-react, and it was one of my favorite open source discoveries of 2021.

I started writing a long response, but I want to add that a simple CRA + JSS + TS (named exports only) stack solves or abstracts away most of these issues.

JSS