postcss-plugins VS PostCSS

the author of the most popular PostCSS plugin himself recommended the postcss-preset-env over his own creation which is cssnex, and

The example in A) won't work as the plugin can't convert the functions with variables in it. https://github.com/csstools/postcss-plugins/tree/main/plugin...

You can use this today if you're using PostCSS in your build process (which is the case if you use autoprefixer)! https://preset-env.cssdb.org/

Switching from a ready-made tool like Sass or a recommendation package like cssnext (deprecated since 2019) or PostCSS Preset Env (archived in 2022), to the modular PostCSS Preset Env plugin set we can choose a helpful and convenient set of future CSS features beyond the current stable client CSS.

To implement :has support, the css-has-pseudo polyfill can be used. This polyfill includes both a PostCSS plugin and a JS function to be used in the HTML page.

Yes, it's behind a flag and only in future versions, but it is a huge step forward. Those versions will soon be available, and we can try it locally (unfortunately, not on production without a polyfill or a plugin).

w/ postcss-preset-env(v7.8.3): convert modern CSS into something most browsers can understand, determining the polyfills you need based on your targeted browsers or runtime environments. It takes the support data that comes from MDN and Can I Use and determine from a browserlist whether those transformations are needed. It also packs Autoprefixer within and shares the list with it, so prefixes are only applied when you're going to need them given your browser support list.

There's a @ custom-media proposal (and PostCSS plugin) that can make it a lot easier to use media queries across components. Define your MQs in your global CSS, use everywhere. If you're worried about repeating MQs in your CSS from a bloat perspective, there are PostCSS plugins for that as well.

The term you are looking for is "nesting". CSS currently does not support it. But there is a draft being worked on. No browser currently supports it, though. Most CSS Pre- or Postprocessors like Sass, Less, Stylus, PostCSS support nesting.

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.