oocss VS PostCSS

Perhaps the most important CSS methodology to emerge during the web’s transition towards application-like websites was Object Oriented CSS (OOCSS), devised by Nicole Sullivan in 2009. Nicole’s now legendary article, ‘The Media Object Saves Hundreds of Lines of Code’, represented a fundamental rethinking on the composition of CSS rulesets and their relationship to HTML content. Instead of writing CSS styles around specific HTML content or basing styles on the location of content within the DOM, OOCSS prioritized writing reusable styling rules based on design patterns (in the case of the media object: ‘a fixed size media element (e.g. image or video) along with other variable size content (e.g. text)’). As perhaps the first instance of a CSS methodology systematically informed by a visual pattern language, OOCSS was also a critical step towards a more modular, reusable approach to writing CSS.

Component based CSS frameworks originating with OOCSS inherently limits selector scope to only elements inside the 'CSS object'.

OOCSS

OOCSS - Object Oriented CSS

OOCSS - (Object-oriented CSS) 2. Use a preprocessor. They fill the lacking features of CSS and helps you write more readable, and smaller reusable pieces of CSS. Some popular preprocessors are: 1. Sass 2. Less 3. Stylus 3. Reduce redundancy. You are using font-weight: bold for the header, but you are also setting it for the div inside. CSS stands for Cascading Style Sheets because styles in CSS are cascading, meaning child elements will inherit styles from parents. 4. Avoid using strong and complex selectors. You are using an id, but a class would do just fine. Having strong selectors means you will have a harder time overriding them later on if needed. 5. Avoid using !important as much as possible. Only use it for utility and helper classes if you must, which need to override anything, such as hiding or displaying an element. 6. Don't use inline CSS, unless your inlining critical CSS. Instead, import styles using a link tag in your head element. (Critical CSS refers to above-the-fold content. Inlining it can help users see a properly rendered page more quicker) 7. Use semantic HTML. You are assigning a header class to a div, which could have been an h1/2/3/n element. This not only helps in terms of accessibility but can also help to improve your SEO score. 8. Use rem for typography. You are using em which cascades, meaning if you set the root element to have 12px, a main element with 2em will have the font size of 24px. If you put a div inside of it with 2em, it will have a font size of 48px, meaning that the size is duplicated. This makes it hard to track down values for deeply nested elements. Instead, use rem which stands for root em, and does not cascade. 9. Make sure your formatting is consistent. You use opening brackets both after a selector and on a new line. Tools like stylelint can help you enforce certain rules to keep your code more consistent, which helps to improve readability and maintainability. 10. Outsource your colors / sizes / spacings into variables. Everything that is bound to change can be in a configuration file to make things more flexible. You can either use CSS variables for this, or a preprocessor. 11. Nothing is written in stone, feel free to come up with your own set of rules that helps you create a more dev-friendly environment. But most importantly, keep things consistent.

✨ BEM 💥 Object Oriented CSS 🌟 Atomic CSS

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.