Note
A decade ago this was the defacto way I implemented CSS on teams. Now this project serves a reference implementation.
Layr is a live ITCSS reference implementation for teams.
Layr is the renamed continuation of the old Obsidian.css project. It is not currently intended for npm republishing; the goal is to keep a working, inspectable implementation of layered CSS architecture that teams can study, adapt, and run locally.
The reset-only level.css sibling is also preserved as a
workspace for projects that need only the common browser baseline.
The live documentation site is published at charliewilco.github.io/layr.
The font-family-only ff.css sibling is preserved as a workspace of
reusable typography utilities.
This project works under the belief that when abstracted most CSS is shockingly similar across projects. More than likely you'll need a type scale, a grid system, spacing utilities, media blocks, sensible default styling for elements (forms, tables, buttons), and a small set of predictable components. Layr keeps those patterns organized as a concrete ITCSS system rather than as a marketing shell.
Styles are written in an adapted BEM naming convention and organized in an ITCSS-like methodology. It uses PostCSS plugins to resolve imports, process custom properties, add vendor prefixes, generate stylesheet metrics, and minify production CSS.
npm install
npm run dev --workspace layr-documentationThe documentation site imports the local layr.css workspace package and renders live examples from the source CSS modules.
The Astro documentation workspace intentionally uses TypeScript 6 because astro check still depends on TypeScript's programmatic compiler API. The standalone TypeScript workspaces use TypeScript 7.
Recommended you use PostCSS and postcss-import.
Example using Gulp.js:
const gulp = require('gulp');
const postcss = require('gulp-postcss');
const atImport = require('postcss-import');
const env = require('postcss-preset-env');
const processors = [atImport, env];
gulp.task('styles', () => {
return (
gulp
.src('path/to/stylesheet')
.pipe(postcss(processors))
// Probably other tasks
.pipe(gulp.dest('path/to/destination'))
);
});In a downstream build, import the local package or copy the layer you want to adapt:
@import 'layr.css/src/settings';
@import 'layr.css/src/generic';
@import 'layr.css/src/elements';
@import 'layr.css/src/objects/layr.grid-columns';@import 'layr.css';
:root {
--headlines: 'Proxima Nova Condensed', Lucida Grande, sans-serif;
--body-text: 'Meta Serif Pro', Charter, serif;
}And things should compile the way you'd expect.
ITCSS (Inverted Triangle CSS) from Harry Roberts, is a way of structuring CSS in such a way that the most general selectors to trickle down to the most specific selectors, as if they're moving from the top of an bottom of a triangle to the pinnacle of it.
In this implementation there are a few differences. Normally in ITCSS, you could have a tools like Sass functions, but most of the tools we'd need are coming in CSS and transpiled by PostCSS plugins.
Objects have minimal visual styling in Layr. This is a set between the reset styling and the component level styling because it's beyond an element.
Settings contain base styles but often module variables are only contained in that module; there are a few exceptions (like shadow values).
Classes in Layr are named with purpose.
Objects, components, and utilities are all prefixed (.o-, .c-, .u-). This leads to clear class names, class names we can search for an outline for QA. It also puts a hard line between objects and components.
Elements are not prefixed (ie. .list, .table) because they extend responsive ability or serve as a opt-in default for an element vs opinionated styling. Classes in layr.forms-ui add specific opinionated styling that's common to projects.
Layr uses responsive suffixes @sm. Responsive targeting shouldn't be a modifier and falls in its own category. Layr defaults to a mobile first approach to CSS, meaning that classes without suffixes apply their styles to all screen sizes and ascend upward for styling per suffix.
@sm, @md, @lg are the given suffixes in Layr.
BEM is a naming convention that gives class names informative and clear meaning.
.block__element--modifier {
/* Declarations */
}
Blocks can be described as squares you can draw around a piece of UI or the root of a module (visual or conceptual). Most block names should be really simple, so avoid abbreviating or complicating. If two words are needed to describe a block separate them with a single hyphen -.
Blocks are the basis of a name. They can have both a modifier and a element attached (.block__element--modifier) or have just have one (either a modifier .block--modifier or an element .block__element.
Utilities in Layr get a specific block name that describes their function. For example d abbreviating display or bkg abbreviating background.
Elements are pieces of a block separated from a block by a double underscore __. .c-modal__close would refer to a close link for a modal component, .o-intrinsic__item would refer to the item in the intrinsic container.
Modifiers add to the block or element in some way, hence modifying it. .o-icon--sm would refer to a small icon object and .o-grid__col--3/12 would refer to a grid column that's 3 parts of 12.
Utility modifiers get a single hyphen -.
First off, you're awesome for wanting to contribute. Second, please take a second to go over a few things to make this process simpler for everyone. Third, you're awesome.
Clone the repository and run the following in the root of the project:
npm install
npm run dev --workspace layr-documentation # open this in one tab
npm run dev --workspace layr.css # open this in anotherThis project uses npm workspaces.
Inside this project there are PostCSS plugins, the core library, and the dev documentation.
pluton.css is preserved here as the lightweight subset that
split from Obsidian.css before the project became Layr. It keeps its historical
source API and builds with the same current PostCSS toolchain as the rest of the
monorepo.
kndlng preserves the JavaScript token helpers that exposed
Obsidian.css values to CSS-in-JS consumers. It keeps the historical Obsidian
2.1.3 token snapshot and builds with TypeScript instead of its historical
Webpack and Babel toolchain.
Reduced test cases are required. All bug reports and problem issues require a reduced test case. See CSS Tricks - Reduced Test Cases on why they "are the absolute, ... number one way to troubleshoot bugs." Reduced test cases help you identify the issue at hand and understand your own code. On our side, they greatly reduce the amount of time spent resolving the issue.
- A reduced test case is an isolated example that demonstrates the bug or issue.
- It contains the bare minimum HTML, CSS, and JavaScript required to demonstrate the bug. No extra functionality or styling.
- A link to your site is not a reduced test case.
- A JSBin or CodePen is preferred so we can help you fix an error.
- Fork this repo.
- Push to your fork and submit a pull request.
- Please provide a short explanation of why you made the changes you made.
MIT
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.