A boilerplate of pre-defined native CSS architecture, styling, and HTML to kickstart your project.
View the docs site to see Roux's base styling for forms, buttons, tables, and typography.
Roux gives you an organized foundation of CSS files, variables, base styles, and simple HTML components so you can start building immediately instead of setting everything up from scratch. It's a structured starting point for writing your own CSS and HTML—not a framework like Tailwind or Material UI. Think of it like a GitHub template repo, but for your stylesheets and basic component markup.
You can cherry-pick what you need, use it for inspiration, or adopt the whole system—whatever works for your project. It's flexible and extendable, but opinionated about what matters. All HTML components aim to be accessible and semantic by default.
You may have used Bitters and Refills in the past—move on over to a fully native setup with Roux.
When you start a new web project, you face a blank CSS file and dozens of decisions:
- How should I organize my styles as the project grows?
- Should I define colors and spacing as variables, or hardcode them?
- Do I need to reset browser defaults?
- How do I structure forms, buttons, and typography consistently?
- Is my HTML accessible?
Without a plan, you may end up with unmaintainable and disorganized CSS files that are not approachable to you or your team. Roux solves this by providing thoughtful defaults and organization patterns that scale with your project.
- Want to write custom CSS (not use a framework like Tailwind or Bootstrap)
- Need a structured starting point instead of a blank stylesheet
- Want consistent design tokens (colors, spacing, fonts) defined upfront as CSS variables
- Are starting a new project or refactoring messy CSS
- Want the flexibility to customize everything to your exact needs
- Prefer utility-first frameworks like Tailwind
- Need advanced JavaScript-heavy UI components
- Already have an established CSS system you're happy with
- Organized file structure: Separate files for forms, typography, buttons, tables, etc.
- CSS custom properties: Colors, spacing, font sizes defined as variables in one place
- Base element styling: Sensible defaults for buttons, forms, tables, and more
- A system to build on: Not a finished product, but a solid foundation you customize
- Baseline HTML components: A set of basic, semantic, accessible UI components
Installation is very hands-off.
-
npx github:thoughtbot/roux init- This will copy all files from src/css into a
cssfolder at the root of your project. Feel free to move or rename depending on your needs, OR
- This will copy all files from src/css into a
-
Copy and paste from the source code, OR
-
Clone this project:
https://github.com/thoughtbot/roux.
After installation:
- Customize your colors: Open
css/base/_variables.cssand change the color values to match your project. - Link the main CSS file: Import or link to
css/app.cssin your HTML. - Start building: Add your component styles in
css/components/. - Copy components: Grab boilerplate component HTML from the docs site
- Compile (optional): Use your preferred CSS compiler to bundle everything into one file
- This project uses lightning CSS to minify and compile the CSS into one file. There are lots of options for CSS compilation, depending on your project setup and your own preferences. If you're using Dart Sass, you'll need to use
@useinstead of@importin your mainapp.cssfile (you'll also need to switch your file types fromcsstoscss). - To compile in this repo, run
npm ithennpm run build(will output into adistfolder).
- This project uses lightning CSS to minify and compile the CSS into one file. There are lots of options for CSS compilation, depending on your project setup and your own preferences. If you're using Dart Sass, you'll need to use
That's it! You now have an organized CSS foundation to build on.
Rails 8 uses Propshaft by default, which does not support CSS @import directives. Even in setups that do support it, the raw @import approach tells the browser to load each file as a separate network request, which hurts performance. A CSS bundler compiles all your imports into a single file, solving both problems.
You're free to use any bundler you prefer, but if you want a "just set this up for me" path, follow our Rails setup guide using cssbundling-rails and PostCSS.
Everything is imported into app.css, which you'll compile into one CSS file (or import directly).
css/
├── reset/
│ └── _normalize.css # Browser resets
├── base/
│ ├── _animations.css # Global animations
│ ├── _buttons.css # Button styles
│ ├── _disclosures.css # Details/summary elements
│ ├── _fonts.css # Font-face declarations
│ ├── _forms.css # Form styling
│ ├── _layout.css # Layout styling
│ ├── _lists.css # List styling
│ ├── _media.css # Images, videos
│ ├── _modal.css # Dialog elements
│ ├── _tables.css # Table styling
│ ├── _typography.css # Typography defaults
│ └── _variables.css # CSS custom properties (colors, spacing, fonts)
├── components/
│ └── (your components here) # Add your own component styles
├── utilities/
│ └── _hide-visually.css # Helper utilities
└── app.css # Imports everything
reset/_normalize.csscomes first in our imports as that overrides some of our browser defaults. We're working on top of the reset. You can add in any more browser resets into that folder and import it. More on resetbase/_variables.cssis one of the outliers of our base files as it stores all of our custom properties. This comes before all of the other base files since it's a dependency. You don't have to change any of these values if you don't want to. However, you'll likely want to at least adjust the colors. More on variablesbase/_fonts.cssis the other outlier as files like_typography.cssmay rely on it. It's commented out for now since it needs an actual font file to work and you may want to remove it if importing a font in a different way. More on fonts- The rest of the base files make use of many of the custom properties and are not dependent on each other. They're currently in ABC order. More on base files
- The
componentsfolder is where you'll put your component-based styles (e.g.components/_card.css). Ensure the import list is in ABC order for readability. - Utilities are last! Right now there's only one utility. Add in any other global utilities you might have that can be applied as a class. You can prepend them with
.u-[utility-name]and give them their own CSS file. More on utilities
Open css/base/_variables.css to customize your project. This is where all your design tokens live. There's some basic setup for colors, spacing, type size, etc. Go in and edit this for your project's needs. Colors may be the only one you need to edit since the other properties are fairly agnostic.
- Define primitive colors with ranges (e.g.,
--color--blue-100through--color--blue-900) - Map primitives to semantic names (e.g.,
--color--primary-base: var(--color--blue-500)) - Use semantic names throughout your CSS
- Follow the naming convention:
--property--variant(e.g.,--color--primary,--space--large,--font-size--small). - Another fun thing you can add to in
:rootis defining dark mode (or light mode) styles with the same conventions.
:root {
--color--beige-100: #f1f1eb;
--color--beige-900: #b2b2a7;
--color--blue-100: #57929e;
--color--blue-900: #164650;
--color--pink-100: #efaf98;
--color--background-base: var(--color--beige-100);
--color--text: var(--color--blue-900);
--color--accent: var(--color--pink-100);
--color--border: var(--color--beige-900);
@media (prefers-color-scheme: dark) {
--color--background-base: var(--color--blue-900);
--color--text: var(--color--beige-100);
--color--border: var(--color--blue-100);
}
}Open css/base/_fonts.css to add your custom fonts. This is a dependency file since other base files may need it to render a font. Currently it's commented out since it's all based on your font files you want to use, but the structure is there. You may declare multiple font files in here. The example in there shows a variable font file with a range of weights so you don't have to define each individual weight.
- Generally,
font-display: swapis a solid default for most fonts so you always fallback to the other fonts defined in your stack while your custom font is loading. - When you define a font in this file, you'll want to add it to a custom property with a stack in your
_variables.cssfile.
/* base/_fonts.css */
@font-face {
font-display: swap;
font-family: "WorkSans";
font-style: normal;
font-weight: 100 900;
src: url("./fonts/work-sans.woff2") format("woff2");
}
@font-face {
font-display: swap;
font-family: "Quincy";
font-style: normal;
font-weight: normal;
src: url("./fonts/quincy.woff2") format("woff2");
}/* base/_variables.css */
:root {
--font-family--body: "WorkSans", system-ui, Arial, sans-serif;
--font-family--display: "Quincy", Times, serif;
}/* base/_typography.css */
body {
font-family: var(--font-family--body);
font-weight: var(--font-weight--normal);
}
h1,
h2,
h3 {
font-family: var(--font-family--display);
font-weight: var(--font-weight--bold);
}Roux uses a classname for a "button" style since it can be applied to both button elements and a elements that want to appear as a button. We've defined a few variants (primary and secondary) to work from. When applying it to an element, use both button and button--{variant}.
View example buttons on the docs site
<button type="button" class="button button--primary">A primary button</button>
<a href="#" class="button button--secondary"> A secondary button link </a>Most form styling relies on how you structure the HTML. In Roux's styling, you should be nesting an input within a label.
View example forms on the docs site
<label for="email">
<span>Your email</span>
<input id="email" type="email" name="email" />
</label>label:has(
input:not([type]),
select,
textarea,
[type="color"],
[type="date"],
[type="datetime"],
[type="datetime-local"],
[type="email"]
/* other selectors */
) {
display: flex;
flex-direction: column;
gap: var(--space--x-small);
}If you prefer to keep those elements separate, you can adjust the CSS in the forms to use the next-sibling combinator (or any other selector of your choice). You'll likely have to make some other declarations or use another element to wrap the label and input.
<label for="email"> Your email </label>
<input id="email" type="email" name="email" />label + :where(
input:not([type]),
select,
textarea,
[type="color"],
[type="date"],
[type="datetime"],
[type="datetime-local"],
[type="email"]
/* other selectors */
) {
display: flex;
flex-direction: column;
gap: var(--space--x-small);
}base/css/_animation.css
Any global animations can go here. Roux's only animation defines smooth scrolling behavior, only if a user hasn't set their motion preference. If a user has reduced motion set on their machine, they should not experience smooth scrolling.
base/css/_disclosures.css
Basic styling for the details and summary elements with a custom details marker caret.
View example disclosures on the docs site
base/css/_layout.css
A blank slate for your layout styles. It only adds margin around the body tag to start but it can be used to contain styles related to the broad layout of what you build.
base/css/_lists.css
Removes list styling (margin, padding, list style) from ordered and unordered lists if there is a class applied. If no class is applied, ols and uls will take on the default browser style. Oftentimes you may find yourself creating a list of components that are highly styled. Semantically, it might make sense to put them in an ordered or unordered list, but you'd have to remove those default styles—thus this opinion.
This also includes some typographic and spacing opinions for definition lists.
base/css/_media.css
Defines pictures, videos, etc. as block elements that should size responsively with your container. Uses :where so you can override specific instances later if needed.
base/css/_modal.css
Default setup and some base styles for dialog elements. This includes some transition declarations as well as ::backdrop styling.
The .slide-in class can be added for a smooth slide-from-bottom transition when opening a modal (and a slide out on close). See the docs site for setup in HTML and Javascript.
View example modals on the docs site
base/css/_tables.css
Rounded border and striped row styling for tables. This also includes classes to make an overflow scroll table for data sets that are wider than the viewport.
View example tables on the docs site
base/css/_typography.css
A fairly unopinionated typographical setup. This isn't a type scale, but some basic defaults such as ensuring headings are bolded and using a pretty text wrap on h1s. This also leverages the base typographic custom properties in body. You can use the --font-size--[variant] custom properties in _variables.css to be more specific about type size.
View example typography on the docs site
This is where you'd put any component-based CSS files. It starts with some baseline components.
components/
├── _alert.css
├── _badge.css
├── _loading-indicator.css
├── _page-footer.css
└── ...
This holds utility-based helpers that can be used globally. The only utility present is .hide-visually which will hide an element visually but still be accessible to a screen reader. It comes with a companion class, .u-hide-visually--focus-unhide which will show an element if focused (by a keyboard for example).
- Add your own utilities following the
.u-[name]pattern.
Bug reports and pull requests are welcome on GitHub at https://github.com/thoughtbot/roux.
Please create a new discussion if you want to share ideas for new features.
This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the code of conduct.
Open source templates are Copyright (c) thoughtbot, inc. It contains free software that may be redistributed under the terms specified in the LICENSE file.
Everyone interacting in Roux's codebases, issue trackers, chat rooms and mailing lists is expected to follow the code of conduct.
This repo is maintained and funded by thoughtbot, inc. The names and logos for thoughtbot are trademarks of thoughtbot, inc.
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