Double Dash Media Queries

Double Dash + PostCSS = the next decade media queries workflow, right now.

Double Dash is a SCSS library helping to declare custom media queries. It includes:

• predefined custom media queries, covering the whole specs;
• mixins that generate ranged media queries (min-width, max-width…).

⚠️ To use double-dash.scss in a node-sass project, see v0.8 documentation. If you’re not sure about your environment, start with the installation section.

Contents

• Installation
• Predefined custom media queries
  • Color scheme (prefers-color-scheme)
  • Connectivity (prefers-reduced-data)
  • Contrast (prefers-contrast)
  • Display (display-mode)
  • Forced colors (forced-colors)
  • Motion (prefers-reduced-motion)
  • Ratio (aspect-ratio)
  • Others
• Mixins for ranged media queries
  • Introduction
  • Available mixins
    • Width and height
    • Resolution
    • Ratio
• Partial import
• Debug

Installation

💡 double-dash.scss supports both the old and the new (2020) SASS specification, but the usage of the library varies per spec.

If you’re not sure which one your project uses, this might help.

• If the project uses node-sass or if you import SCSS files using @import, there’s a high chance you use the old spec.
• If the project uses Dart SASS (sass) and if you import SCSS files using @use or @forward, you are using the new spec.
• In the new spec, @import is deprecated and variables are not global. This is why double.dash.scss usage isn’t the same changes depending on the spec.

Projects using Dart SASS

Dart SASS support starts at version 1.0.

• npm install double-dash.scss pulls the package into your project;
• @use 'double-dash.scss' as mq; in all projects where you need one of its mixins or variables. mq is the recommended namespace for double-dash.scss.

Projects using node-sass

Projects using node-sass must stick to version 0.x

• npm install double-dash.scss@0 pulls the package into your project;
• @import 'double-dash.scss'; near the beginning of the main SCSS file enables Double Dash features.

Browser support

💡 Awaiting for browsers to embrace Custom Media Queries, PostCSS Preset Env is perfect to fill the gap. If you need an example of a small project using both double-dash.scss and PostCSS, you can have a look at Can We repository.

Predefined custom media queries

Double Dash provides a set of custom media queries usable in @media rules out of the box.

Colors scheme (prefers-color-scheme)

--dark: the user prefers a dark UI.

--light: the user prefers a light UI or has no colors preference. Aliases: --any-theme, --any-color-scheme, --no-theme-preference, --no-color-scheme-preference.

Example:

html {
  background: white;
  color: black;

  @media (--dark) {
    background: black;
    color: white;
  }
}

Contrast (prefers-contrast)

--more-contrast: the user prefers a UI with a higher level of contrast. Aliases: --high-contrast, --contrasted.

--less-contrast: the user prefers a UI with a lower level of contrast. Alias: --low-contrast.

--no-contrast-preference: the user has no contrast preference. Aliases: --any-contrast, --normal-contrast.

Connectivity (prefers-reduced-data)

--reduced-data: the user prefers to save data. Alias: --data-shortage.

--no-data-preference: the user doesn’t prefer to save data. Alias: --data.

Example:

.hero {
  background-image: url('wedding-pic-2048-1024.webp');

  @media (--reduced-data) {
    background-image: none;
  }
}

Display (display-mode)

These custom media queries matches the Web Manifest display property.

--fullscreen: the website covers the screen, the browser has no chrome (= no user interface).

--standalone: the website is displayed as if it was an app.

--minimal-ui: same as standalone, with some browser UI elements.

--browser: the website is open in a browser tab or window.

Forced colors (forced-colors)

These two custom media queries are not released, yet.

--forced-colors: the available colors are limited to a user-chosen color palette.

--no-forced-colors: the available colors are not restricted by a user-chosen color palette.

Motion (prefers-reduced-motion)

--reduced-motion: the user wants less or no animation. Aliases: --no-motion, --less-motion, --stop.

--no-motion-preference: the user doesn’t want less animation. Aliases: --motion, --full-motion, --play, --animate-all-the-things, --party-parrot.

Example:

*,
*::before,
*::after {
  @media (--reduced-motion) {
    transition-duration: 0.001s !important;
    animation-duration: 0.001s !important;
  }
}

Ratio (aspect-ratio)

--landscape: the viewport width is greater than its height. Alias: --horizontal.

--square: the viewport width and height are equal.

--portrait: the viewport width is smaller than its height. Alias: --vertical.

Others

Not documented yet. Feel free to have a messy look at the messy sources.

Mixins for ranged media queries

Introduction

Mixins for ranged media queries generate a lot of custom media queries based on breakpoints lists.

@use 'double-dash.scss' as mq;

// Gather component breakpoints in a SCSS list.
$nav-breakpoints: (
  'nav-collapsed': 45em,
  'nav-expanded': 90em,
);

// One mixin to generate them all.
@include mq.w($nav-breakpoints);

This unique w mixin call generates the following width-based custom media queries:

// min-width
--nav-collapsed // (min-width: 45em)
--nav-expanded // (min-width: 90em)

// max-width
--to-nav-collapsed // (max-width: 44.999em)
--to-nav-expanded // (max-width: 89.999em)

// combinations
--nav-collapsed-to-nav-expanded // (min-width: 45em) and (max-width: 89.999em)

They are now all usable in @media:

@media (--nav-expanded) {
  .nav-toggle-btn { display: none; }
}

Available mixins

Width and height

@use 'double-dash.scss' as mq;

@include mq.w-from(name, width);
@include mq.w-to(name, width);
@include mq.w-is(name, width);
@include mq.w-from-to(name, smallerWidth, otherName, greaterWidth);
@include mq.w(widthsList);

@include mq.h-from(name, height);
@include mq.h-to(name, height);
@include mq.h-is(name, height);
@include mq.h-from-to(name, smallerHeight, otherName, greaterHeight);
@include mq.h(heightsList);

Width and height mixins documentation.

Resolution

@use 'double-dash.scss' as mq;

@include mq.resolution-from(name, pxDensityFactor);
@include mq.resolution-to(name, pxDensityFactor);
@include mq.resolution-is(name, pxDensityFactor);
@include mq.resolution(resolutionsList);

Resolution mixins documentation.

Ratio

Soon.

Partial import

The purpose of partial import is to avoid naming conflicts with existing custom media queries and SCSS mixins.

Import predefined custom media queries

This examples only pulls the prefers-reduced-motion custom media queries:

@use 'double-dash.scss/src/variables/motion';

Available files: color, js, light, motion, pointer, ratio, refresh, resolution, ui.

Import mixins for ranged media queries

Example for the resolution mixins:

@use 'double-dash.scss/src/mixins/sizes' as mq;

Available files: ratio, resolution, sizes.

Debug

You can output each custom media query generated with Double Dash in your CLI by setting the $debug variable when importing Double Dash.

@use 'double-dash.scss' with ($debug: true);