Css media screen viewport

CSS Media Queries

The @media rule, introduced in CSS2, made it possible to define different style rules for different media types.

Examples: You could have one set of style rules for computer screens, one for printers, one for handheld devices, one for television-type devices, and so on.

Unfortunately these media types never got a lot of support by devices, other than the print media type.

CSS3 Introduced Media Queries

Media queries in CSS3 extended the CSS2 media types idea: Instead of looking for a type of device, they look at the capability of the device.

Media queries can be used to check many things, such as:

  • width and height of the viewport
  • width and height of the device
  • orientation (is the tablet/phone in landscape or portrait mode?)
  • resolution

Using media queries are a popular technique for delivering a tailored style sheet to desktops, laptops, tablets, and mobile phones (such as iPhone and Android phones).

Browser Support

The numbers in the table specifies the first browser version that fully supports the @media rule.

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Media Query Syntax

A media query consists of a media type and can contain one or more expressions, which resolve to either true or false.

The result of the query is true if the specified media type matches the type of device the document is being displayed on and all expressions in the media query are true. When a media query is true, the corresponding style sheet or style rules are applied, following the normal cascading rules.

Unless you use the not or only operators, the media type is optional and the all type will be implied.

You can also have different stylesheets for different media:

CSS3 Media Types

Value Description
all Used for all media type devices
print Used for printers
screen Used for computer screens, tablets, smart-phones etc.
speech Used for screenreaders that «reads» the page out loud

Media Queries Simple Examples

One way to use media queries is to have an alternate CSS section right inside your style sheet.

The following example changes the background-color to lightgreen if the viewport is 480 pixels wide or wider (if the viewport is less than 480 pixels, the background-color will be pink):

Example

The following example shows a menu that will float to the left of the page if the viewport is 480 pixels wide or wider (if the viewport is less than 480 pixels, the menu will be on top of the content):

Example

More Media Query Examples

For much more examples on media queries, go to the next page: CSS MQ Examples.

CSS @media Reference

For a full overview of all the media types and features/expressions, please look at the @media rule in our CSS reference.

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Using media queries

Media queries allow you to apply CSS styles depending on a device’s general type (such as print vs. screen) or other characteristics such as screen resolution or browser viewport width. Media queries are used for the following:

  • To conditionally apply styles with the CSS@media and @importat-rules.
  • To target specific media for the , , , and other HTML elements with the media= attribute.
  • To test and monitor media states using the Window.matchMedia() and EventTarget.addEventListener() methods.

Note: The examples on this page use CSS’s @media for illustrative purposes, but the basic syntax remains the same for all types of media queries.

Syntax

A media query is composed of an optional media type and any number of media feature expressions, which may optionally be combined in various ways using logical operators. Media queries are case-insensitive.

  • Media types define the broad category of device for which the media query applies: all , print , screen . The type is optional (assumed to be all ) except when using the not or only logical operators.
  • Media features describe a specific characteristic of the user agent, output device, or environment:
    • any-hover
    • any-pointer
    • aspect-ratio
    • color
    • color-gamut
    • color-index
    • device-aspect-ratio Deprecated
    • device-height Deprecated
    • device-width Deprecated
    • display-mode
    • dynamic-range
    • forced-colors
    • grid
    • height
    • hover
    • inverted-colors
    • monochrome
    • orientation
    • overflow-block
    • overflow-inline
    • pointer
    • prefers-color-scheme
    • prefers-contrast
    • prefers-reduced-motion
    • prefers-reduced-transparency Experimental
    • resolution
    • scripting
    • update
    • video-dynamic-range
    • width .

    A media query computes to true when the media type (if specified) matches the device on which a document is being displayed and all media feature expressions compute as true. Queries involving unknown media types are always false.

    Note: A style sheet with a media query attached to its tag will still download even if the query returns false , the download will happen but the priority of downloading will be much lower. Nevertheless, its contents will not apply unless and until the result of the query changes to true . You can read why this happens in Tomayac’s blog Why Browser Download Stylesheet with Non-Matching Media Queries.

    Targeting media types

    Media types describe the general category of a given device. Although websites are commonly designed with screens in mind, you may want to create styles that target special devices such as printers or audio-based screen readers. For example, this CSS targets printers:

    You can also target multiple devices. For instance, this @media rule uses two media queries to target both screen and print devices:

    See media type for a list of all media types. Because they describe devices in only very broad terms, just a few are available; to target more specific attributes, use media features instead.

    Targeting media features

    Media features describe the specific characteristics of a given user agent, output device, or environment. For instance, you can apply specific styles to widescreen monitors, computers that use mice, or to devices that are being used in low-light conditions. This example applies styles when the user’s primary input mechanism (such as a mouse) can hover over elements:

    Many media features are range features, which means they can be prefixed with «min-» or «max-» to express «minimum condition» or «maximum condition» constraints. For example, this CSS will apply styles only if your browser’s viewport width is equal to or narrower than 1250px:

    If you create a media feature query without specifying a value, the nested styles will be used as long as the feature’s value is not zero (or none , in Level 4). For example, this CSS will apply to any device with a color screen:

    If a feature doesn’t apply to the device on which the browser is running, expressions involving that media feature are always false.

    For more Media feature examples, please see the reference page for each specific feature.

    Creating complex media queries

    Sometimes you may want to create a media query that depends on multiple conditions. This is where the logical operators come in: not , and , and only . Furthermore, you can combine multiple media queries into a comma-separated list; this allows you to apply the same styles in different situations.

    In the previous example, we’ve already seen the and operator used to group a media type with a media feature. The and operator can also combine multiple media features into a single media query. The not operator, meanwhile, negates a media query, basically reversing its normal meaning. The only operator prevents older browsers from applying the styles.

    Note: In most cases, the all media type is used by default when no other type is specified. However, if you use the not or only operators, you must explicitly specify a media type.

    Combining multiple types or features

    The and keyword combines a media feature with a media type or other media features. This example combines two media features to restrict styles to landscape-oriented devices with a width of at least 30 ems:

    @media (min-width: 30em) and (orientation: landscape)  /* … */ > 

    To limit the styles to devices with a screen, you can chain the media features to the screen media type:

    @media screen and (min-width: 30em) and (orientation: landscape)  /* … */ > 

    Testing for multiple queries

    You can use a comma-separated list to apply styles when the user’s device matches any one of various media types, features, or states. For instance, the following rule will apply its styles if the user’s device has either a minimum height of 680px or is a screen device in portrait mode:

    @media (min-height: 680px), screen and (orientation: portrait)  /* … */ > 

    Taking the above example, if the user had a printer with a page height of 800px, the media statement would return true because the first query would apply. Likewise, if the user were on a smartphone in portrait mode with a viewport height of 480px, the second query would apply and the media statement would still return true.

    Inverting a query’s meaning

    The not keyword inverts the meaning of an entire media query. It will only negate the specific media query it is applied to. (Thus, it will not apply to every media query in a comma-separated list of media queries.) The not keyword can’t be used to negate an individual feature query, only an entire media query. The not is evaluated last in the following query:

    @media not all and (monochrome)  /* … */ > 

    This means that the above query is evaluated like this:

    @media not (all and (monochrome))  /* … */ > 

    It wouldn’t be evaluated like this:

    @media (not all) and (monochrome)  /* … */ > 

    As another example, the following media query:

    @media not screen and (color), print and (color)  /* … */ > 

    This means that the above query is evaluated like this:

    @media (not (screen and (color))), print and (color)  /* … */ > 

    Improving compatibility with older browsers

    The only keyword prevents older browsers that do not support media queries with media features from applying the given styles. It has no effect on modern browsers.

    @media only screen and (color)  /* … */ > 

    Syntax improvements in Level 4

    The Media Queries Level 4 specification includes some syntax improvements to make media queries using features that have a «range» type, for example width or height, less verbose. Level 4 adds a range context for writing such queries. For example, using the max- functionality for width we might write the following:

    Note: The Media Queries Level 4 specification has reasonable support in modern browsers, but some media features are not well supported. See the @media browser compatibility table for more details.

    In Media Queries Level 4 this can be written as:

    Using min- and max- we might test for a width between two values like so:

    @media (min-width: 30em) and (max-width: 50em)  /* … */ > 

    This would convert to the Level 4 syntax as:

    Media Queries Level 4 also adds ways to combine media queries using full boolean algebra with and, not, and or.

    Negating a feature with not

    Using not() around a media feature negates that feature in the query. For example, not(hover) would match if the device had no hover capability:

    Testing for multiple features with or

    You can use or to test for a match among more than one feature, resolving to true if any of the features are true. For example, the following query tests for devices that have a monochrome display or hover capability:

    See also

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    This page was last modified on Jun 23, 2023 by MDN contributors.

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