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Media Queries CSS media queries allow us to adjust the display and orientation of content at different screen sizes. gqqi2cqlST8 scss/util/_breakpoint.scss js/foundation.util.mediaQuery.js
breakpoints

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Default Media Queries

Foundation for Sites has three core breakpoints:

  • Small: any screen.
  • Medium: any screen 640 pixels or wider.
  • Large: any screen 1024 pixels or wider.

Many components can be modified at different screen sizes using special breakpoint classes. The grid is the most obvious example. In the code below, the left-hand column is six columns wide on small screens, hence .small-6. On medium-sized screens, the class .medium-4 overrides the small style, changing the column to be four wide.

<div class="grid-x grid-margin-x">
  <div class="cell small-6 medium-4"></div>
  <div class="cell small-6 medium-8"></div>
</div>

If you're using the CSS version of Foundation, use these media queries to imitate the three core breakpoints:

/* Small only */
@media screen and (max-width: 39.9375em) {}

/* Medium and up */
@media screen and (min-width: 40em) {}

/* Medium only */
@media screen and (min-width: 40em) and (max-width: 63.9375em) {}

/* Large and up */
@media screen and (min-width: 64em) {}

/* Large only */
@media screen and (min-width: 64em) and (max-width: 74.9375em) {}

Upgrading from Foundation 5

In Foundation 5, breakpoints were accessed using a series of Sass variables named $small-up, $small-only, $medium-only, and so on. In Foundation 6, this method of writing media queries has been replaced with a dedicated breakpoint mixin, described below. The legacy variables will be removed in Foundation 6.3.

To upgrade your existing media queries, replace rulesets like this:

@media #{$medium-only} {
}

With this:

@include breakpoint(medium only) {
}

Changing the Breakpoints

If you're using the Sass version of Foundation, the default breakpoints can be changed. The names of the breakpoints, and their widths, are stored in a $breakpoints variable in the settings file.

$breakpoints: (
  small: 0px,
  medium: 640px,
  large: 1024px,
  xlarge: 1200px,
  xxlarge: 1440px,
);

Even though the above values are in pixels, they're converted to ems at the end for use in media queries.

Changing the widths of any of the breakpoints is as easy as changing the pixel values in this map. Note that here there are two extra breakpoints: xlarge and xxlarge. We don't use these for any components, and also don't output any CSS classes that use them by default.

You can change that by modifying the $breakpoint-classes variable in your settings file. This is a list of breakpoint names. Adding or removing names from the list will change the CSS class output. It looks like this by default:

$breakpoint-classes: (small medium large);

For example, to get .xlarge classes in your CSS, for use in the grid, Menu, and more, just add it to the end of the list:

$breakpoint-classes: (small medium large xlarge);

Sass

The Breakpoint Mixin

Our breakpoint() mixin makes it easy to write media queries. You can use the named breakpoints, or a custom pixel, rem, or em value.

To use the mixin, call it with @include, and then include the CSS content you want inside the curly braces.

.element {
  // Only affects medium screens and larger
  @include breakpoint(medium) {
    // All CSS in here goes inside the media query
  }
}

The behavior of the media query can be changed by adding the keyword down or only after the breakpoint value, separated by a space.

.element {
  // Only affects medium screens and smaller
  @include breakpoint(medium down) { }
  // Only affects medium screens, not small or large
  @include breakpoint(medium only) { }
}

It's also possible to pass in custom values. You can enter a pixel, rem, or em value—all values are converted to em at the end.

.element {
  // Converted to 20em
  @include breakpoint(320px) { }
  // Unitless values are assumed to be pixels
  @include breakpoint(320) { }
  // Converted to 40em
  @include breakpoint(40rem) { }
}

Lastly, there are three special media queries that are not width-based: portrait, landscape, and retina. Using these keywords with the breakpoint() mixin will output a media query for device orientation or pixel density, rather than screen width.

.element {
  @include breakpoint(landscape) {
    // CSS for landscape-oriented devices only
  }
  @include breakpoint(retina) {
    // CSS for high-resolution displays only
  }
}

Breakpoint Function

The functionality of the breakpoint() mixin comes from an internal function, also called breakpoint(). If you want to write your own media queries, you can use the breakpoint() function to access the logic of the mixin directly.

@media screen and #{breakpoint(medium)} {
  // Medium and up styles
}

This can be used to combine multiple media queries together.

@media screen and #{breakpoint(medium)} and #{breakpoint(xlarge down)} {
  // Medium to extra large styles
}

JavaScript

Working with Media Queries

The Foundation JavaScript includes a set of helper functions for working with media queries. They're all on the Foundation.MediaQuery object.

The MediaQuery utility uses the Sass breakpoint settings and requires the Foundation CSS to be imported. For Sass users, you need to include either `foundation-everything()` or `foundation-global-styles()`.

Get the name of the current breakpoint with MediaQuery.current.

Foundation.MediaQuery.current // => 'small', 'medium', etc.

To see if the screen is currently a certain breakpoint or larger, use MediaQuery.atLeast.

if (Foundation.MediaQuery.atLeast('medium')) {
  // True if medium or large
  // False if small
}

To see if the screen is currently a certain breakpoint, use MediaQuery.is.

if (Foundation.MediaQuery.is('small only')) {
  // True if small
  // False if medium or large
}

To get the media query of a breakpoint, use MediaQuery.get.

Foundation.MediaQuery.get('medium') // => only screen and (min-width: 640px)

Watching for Breakpoint Changes

The media query helper broadcasts an event on the window every time the breakpoint changes. We use this internally with plugins like Interchange to detect a shift in breakpoint. You can also subscribe to the event yourself.

$(window).on('changed.zf.mediaquery', function(event, newSize, oldSize) {
  // newSize is the name of the now-current breakpoint, oldSize is the previous breakpoint
});