Css — медиа запросы (media queries)

Definition and Usage

The rule is used in media queries to apply different styles for different media types/devices.

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 (responsive web design) to desktops, laptops, tablets, and mobile phones.

You can also use media queries to specify that certain styles are only for printed documents or for screen readers (mediatype: print, screen, or speech).

In addition to media types, there are also media features. Media features
provide more specific details to media queries, by allowing to test for a
specific feature of the user agent or display device. For example, you
can apply styles to only those screens that are greater, or smaller, than a
certain width.

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

@media screen and (min-width: 480px) {  body {
    background-color: lightgreen;  }}

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

@media screen and (min-width: 480px) {  #leftsidebar
{width: 200px; float: left;}  #main
{margin-left: 216px;}}

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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Media Queries

A media query consists of a media type and zero or more expressions that check for the
conditions of particular media
features.

Statements regarding media queries in this section assume the is followed. Media queries that do not
conform to the syntax are discussed in the . I.e. the syntax takes precedence over requirements
in this section.

Here is a simple example written in HTML:

This example expresses that a certain style sheet
() applies to devices of a certain media type
(‘’) with certain feature (it
must be a color screen).

Here the same media query written in an @import-rule in CSS:

A media query is a logical expression that is either true or false. A
media query is true if the media type of the media query matches the media
type of the device where the user agent is running (as defined in the
«Applies to» line), and all expressions in the media query are true.

A shorthand syntax is offered for media queries that apply to all media
types; the keyword ‘’ can be left
out (along with the trailing ‘’).
I.e. if the media type is not explicitly given it is ‘’.

I.e. these are identical:

As are these:

Several media queries can be combined in a media query list. A
comma-separated list of media queries. If one or more of the media queries
in the comma-separated list are true, the whole list is true, and
otherwise false. In the media queries syntax, the comma expresses a
logical OR, while the ‘’ keyword
expresses a logical AND.

Here is an example of several media queries in a comma-separated list
using the an @media-rule in CSS:

If the media query list is empty (i.e. the declaration is the empty
string or consists solely of whitespace) it evaluates to true.

I.e. these are equivalent:

The logical NOT can be expressed through the ‘’ keyword. The presence of the keyword
‘’ at the beginning of the media
query negates the result. I.e., if the media query had been true without
the ‘’ keyword it will become false,
and vice versa. User agents that only support media types (as described in
HTML4) will not recognize the ‘’
keyword and the associated style sheet is therefore not applied.

The keyword ‘’ can also be used
to hide style sheets from older user agents. User agents must process
media queries starting with ‘’ as
if the ‘’ keyword was not present.

The media queries syntax can be used with HTML, XHTML, XML and the
@import and @media rules of CSS.

Here is the same example written in HTML, XHTML, XML, @import and
@media:

The specification has not
yet been updated to use media queries in the
pseudo-attribute.

If a media feature does not apply to the device where the UA is running,
expressions involving the media feature will be false.

The media feature ‘’ only applies to visual
devices. On an aural device, expressions involving ‘’ will therefore always be
false:

Expressions will always be false if the unit of measurement does not
apply to the device.

The ‘’ unit does not apply to
‘’ devices so the following
media query is always false:

Note that the media queries in this example would have been true if the
keyword ‘’ had been added to the
beginning of the media query.

To avoid circular dependencies, it is never necessary to apply the style
sheet in order to evaluate expressions. For example, the aspect ratio of a
printed document may be influenced by a style sheet, but expressions
involving ‘’ will be
based on the default aspect ratio of the user agent.

User agents are expected, but not required, to re-evaluate
and re-layout the page in response to changes in the user environment, for
example if the device is tilted from landscape to portrait mode.

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CSS Properties

align-content
align-items
align-self
all
animation
animation-delay
animation-direction
animation-duration
animation-fill-mode
animation-iteration-count
animation-name
animation-play-state
animation-timing-function

backface-visibility
background
background-attachment
background-blend-mode
background-clip
background-color
background-image
background-origin
background-position
background-repeat
background-size
border
border-bottom
border-bottom-color
border-bottom-left-radius
border-bottom-right-radius
border-bottom-style
border-bottom-width
border-collapse
border-color
border-image
border-image-outset
border-image-repeat
border-image-slice
border-image-source
border-image-width
border-left
border-left-color
border-left-style
border-left-width
border-radius
border-right
border-right-color
border-right-style
border-right-width
border-spacing
border-style
border-top
border-top-color
border-top-left-radius
border-top-right-radius
border-top-style
border-top-width
border-width
bottom
box-decoration-break
box-shadow
box-sizing
break-after
break-before
break-inside

caption-side
caret-color
@charset
clear
clip
clip-path
color
column-count
column-fill
column-gap
column-rule
column-rule-color
column-rule-style
column-rule-width
column-span
column-width
columns
content
counter-increment
counter-reset
cursor

direction
display
empty-cells
filter
flex
flex-basis
flex-direction
flex-flow
flex-grow
flex-shrink
flex-wrap
float
font
@font-face
font-family
font-feature-settings
font-kerning
font-size
font-size-adjust
font-stretch
font-style
font-variant
font-variant-caps
font-weight

gap
grid
grid-area
grid-auto-columns
grid-auto-flow
grid-auto-rows
grid-column
grid-column-end
grid-column-gap
grid-column-start
grid-gap
grid-row
grid-row-end
grid-row-gap
grid-row-start
grid-template
grid-template-areas
grid-template-columns
grid-template-rows

hanging-punctuation
height
hyphens
@import
isolation
justify-content
@keyframes
left
letter-spacing

line-height
list-style
list-style-image
list-style-position
list-style-type

margin
margin-bottom
margin-left
margin-right
margin-top
max-height
max-width
@media
min-height
min-width
mix-blend-mode

object-fit
object-position
opacity
order
outline
outline-color
outline-offset
outline-style
outline-width
overflow
overflow-x
overflow-y

padding
padding-bottom
padding-left
padding-right
padding-top
page-break-after
page-break-before
page-break-inside
perspective
perspective-origin
pointer-events
position
quotes

resize
right
row-gap

scroll-behavior

tab-size
table-layout
text-align
text-align-last
text-decoration
text-decoration-color
text-decoration-line
text-decoration-style
text-indent
text-justify
text-overflow
text-shadow
text-transform
top

transform
transform-origin
transform-style
transition
transition-delay
transition-duration
transition-property
transition-timing-function

unicode-bidi
user-select

vertical-align
visibility

white-space
width
word-break
word-spacing
word-wrap
writing-mode

z-index

Media Features

Value Description
any-hover Does any available input mechanism allow the user to hover over
elements? (added in Media Queries Level 4)
any-pointer Is any available input mechanism a pointing device, and if so, how
accurate is it? (added in Media Queries Level 4)
aspect-ratio The ratio between the width and the height of the viewport
color The number of bits per color component for the output device
color-gamut The approximate range of colors that are supported by the user agent and
output device (added in Media Queries Level 4)
color-index The number of colors the device can display
grid Whether the device is a grid or bitmap
height The viewport height
hover Does the primary input mechanism allow the user to hover over elements?
(added in Media Queries Level 4)
inverted-colors Is the browser or underlying OS inverting colors? (added in Media
Queries Level 4)
light-level Current ambient light level (added in Media Queries Level 4)
max-aspect-ratio The maximum ratio between the width and the height of the display area
max-color The maximum number of bits per color component for the output device
max-color-index The maximum number of colors the device can display
max-height The maximum height of the display area, such as a browser window
max-monochrome The maximum number of bits per «color» on a monochrome (greyscale) device
max-resolution The maximum resolution of the device, using dpi or dpcm
max-width The maximum width of the display area, such as a browser window
min-aspect-ratio The minimum ratio between the width and the height of the display area
min-color The minimum number of bits per color component for the output device
min-color-index The minimum number of colors the device can display
min-height The minimum height of the display area, such as a browser window
min-monochrome The minimum number of bits per «color» on a monochrome (greyscale) device
min-resolution The minimum resolution of the device, using dpi or dpcm
min-width The minimum width of the display area, such as a browser window
monochrome The number of bits per «color» on a monochrome (greyscale) device
orientation The orientation of the viewport (landscape or portrait mode)
overflow-block How does the output device handle content that overflows the viewport along the block axis (added in Media Queries Level 4)
overflow-inline Can content that overflows the viewport along the inline axis be scrolled (added in Media Queries Level 4)
pointer Is the primary input mechanism a pointing device, and if so, how
accurate is it? (added in Media Queries Level 4)
resolution The resolution of the output device, using dpi or dpcm
scan The scanning process of the output device
scripting Is scripting (e.g. JavaScript) available? (added in Media Queries Level
4)
update How quickly can the output device modify the appearance of the content (added in Media Queries Level 4)
width The viewport width

Typical Device Breakpoints

There are tons of screens and devices with different heights and widths, so it is hard to create an exact breakpoint for each device. To keep things simple you could target
five groups:

Example

/*
Extra small devices (phones, 600px and down) */@media only screen and (max-width: 600px)
{…} /* Small devices (portrait tablets and large phones, 600px and up)
*/@media only screen and (min-width: 600px) {…} /* Medium devices (landscape tablets, 768px and up) */
@media only screen and (min-width: 768px) {…} /* Large devices (laptops/desktops, 992px and up)
*/
@media only screen and (min-width: 992px) {…} /* Extra large devices (large
laptops and desktops,
1200px and up) */@media only screen and (min-width: 1200px) {…}

Units

The units used in media queries are the same as in other parts of CSS.
For example, the pixel unit represents CSS pixels and not physical pixels.

Relative units in media queries are based on the initial value, which
means that units are never based on results of declarations. For example,
in HTML, the ‘’ unit is relative to
the initial value of ‘’.

6.1. Resolution

The ‘’ and ‘’ units describe the resolution of an output
device, i.e., the density of device pixels. Resolution unit identifiers
are:

dpi

dots per CSS ‘’

dpcm

dots per CSS ‘’

In this specification, these units are only used in the ‘’ media feature.

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.

@media not|only mediatype and (expressions) {  CSS-Code;}

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
type will be implied.

You can also have different stylesheets for different media:

<link rel=»stylesheet» media=»mediatype and|not|only (expressions)»
href=»print.css»>

CSS Properties

align-contentalign-itemsalign-selfallanimationanimation-delayanimation-directionanimation-durationanimation-fill-modeanimation-iteration-countanimation-nameanimation-play-stateanimation-timing-functionbackface-visibilitybackgroundbackground-attachmentbackground-blend-modebackground-clipbackground-colorbackground-imagebackground-originbackground-positionbackground-repeatbackground-sizeborderborder-bottomborder-bottom-colorborder-bottom-left-radiusborder-bottom-right-radiusborder-bottom-styleborder-bottom-widthborder-collapseborder-colorborder-imageborder-image-outsetborder-image-repeatborder-image-sliceborder-image-sourceborder-image-widthborder-leftborder-left-colorborder-left-styleborder-left-widthborder-radiusborder-rightborder-right-colorborder-right-styleborder-right-widthborder-spacingborder-styleborder-topborder-top-colorborder-top-left-radiusborder-top-right-radiusborder-top-styleborder-top-widthborder-widthbottombox-decoration-breakbox-shadowbox-sizingbreak-afterbreak-beforebreak-insidecaption-sidecaret-color@charsetclearclipclip-pathcolorcolumn-countcolumn-fillcolumn-gapcolumn-rulecolumn-rule-colorcolumn-rule-stylecolumn-rule-widthcolumn-spancolumn-widthcolumnscontentcounter-incrementcounter-resetcursordirectiondisplayempty-cellsfilterflexflex-basisflex-directionflex-flowflex-growflex-shrinkflex-wrapfloatfont@font-facefont-familyfont-feature-settingsfont-kerningfont-sizefont-size-adjustfont-stretchfont-stylefont-variantfont-variant-capsfont-weightgapgridgrid-areagrid-auto-columnsgrid-auto-flowgrid-auto-rowsgrid-columngrid-column-endgrid-column-gapgrid-column-startgrid-gapgrid-rowgrid-row-endgrid-row-gapgrid-row-startgrid-templategrid-template-areasgrid-template-columnsgrid-template-rowshanging-punctuationheighthyphens@importisolationjustify-content@keyframesleftletter-spacingline-heightlist-stylelist-style-imagelist-style-positionlist-style-typemarginmargin-bottommargin-leftmargin-rightmargin-topmax-heightmax-width@mediamin-heightmin-widthmix-blend-modeobject-fitobject-positionopacityorderoutlineoutline-coloroutline-offsetoutline-styleoutline-widthoverflowoverflow-xoverflow-ypaddingpadding-bottompadding-leftpadding-rightpadding-toppage-break-afterpage-break-beforepage-break-insideperspectiveperspective-originpointer-eventspositionquotesresizerightrow-gapscroll-behaviortab-sizetable-layouttext-aligntext-align-lasttext-decorationtext-decoration-colortext-decoration-linetext-decoration-styletext-indenttext-justifytext-overflowtext-shadowtext-transformtoptransformtransform-origintransform-styletransitiontransition-delaytransition-durationtransition-propertytransition-timing-functionunicode-bidiuser-selectvertical-alignvisibilitywhite-spacewidthword-breakword-spacingword-wrapwriting-modez-index

More Examples

Example

Hide an element when the browser’s width is 600px wide or less:

@media screen and (max-width: 600px) {  div.example {    display:
none; 
}}

Example

Use mediaqueries to set the background-color to lavender if the viewport is
800 pixels wide or wider, to lightgreen if the viewport is between 400 and 799 pixels wide.
If the viewport is smaller than 400 pixels, the background-color is lightblue:

body {  background-color: lightblue;}@media screen and (min-width:
400px) {  body {   
background-color: lightgreen;  }}@media
screen and (min-width: 800px) {  body {   
background-color: lavender;  }}

Example

Create a responsive navigation menu (displayed horizontally on large screens and vertically on small screens):

@media screen and (max-width: 600px) {  .topnav a {   
float: none;    width: 100%; 
}}

Example

Use media queries to create a responsive column layout:

/* On screens that are 992px wide or less, go from four columns to two
columns */@media screen and (max-width: 992px) {  .column {   
width: 50%;  }}/* On screens that are 600px wide or less, make the columns stack
on top of each other instead of next to each other */@media screen and (max-width:
600px) {  .column {    width: 100%;
  }}

Example

Use media queries to create a responsive website:

Example

Media queries can also be used to change layout of a page depending on the
orientation of the browser. You can have a set of CSS properties that will only
apply when the browser window is wider than its height, a so called «Landscape»
orientation.

Use a lightblue background color if the orientation is in landscape mode:

@media only screen and (orientation:
landscape) {  body {
   
background-color: lightblue;  }}

Example

Use mediaqueries to set the text color to green when the document is
displayed on the screen, and to black when it is printed:

@media screen {  body {   
color: green;   }}@media print {  body {    color: black;
  }}

Example

Comma separated list: add an additional media query to an already existing one, using a comma (this will behave like an OR operator):

/* When the width is between 600px and 900px OR above 1100px — change the
appearance of <div> */@media screen and (max-width: 900px) and
(min-width: 600px), (min-width: 1100px) {  div.example {   
font-size: 50px;    padding: 50px;   
border: 8px solid black;    background: yellow; 
}}

Media Queries For Menus

In this example, we use media queries to create a responsive navigation menu, that varies
in design on different screen sizes.

Large screens:

Home
Link 1
Link 2
Link 3

Small screens:

Home
Link 1
Link 2
Link 3

Example

/* The navbar container */.topnav {  overflow: hidden; 
background-color: #333;}/* Navbar links */.topnav a {  float:
left;  display: block;  color:
white;  text-align: center;  padding: 14px 16px;
  text-decoration: none;}
/* On screens that are 600px wide or less, make the menu links stack on top
of each other instead of next to each other */@media screen and (max-width: 600px) {
 
.topnav a {    float: none;    width:
100%;  }}

CSS Advanced

CSS Rounded CornersCSS Border ImagesCSS BackgroundsCSS ColorsCSS Color KeywordsCSS Gradients
Linear Gradients
Radial Gradients

CSS Shadows
Shadow Effects
Box Shadow

CSS Text EffectsCSS Web FontsCSS 2D TransformsCSS 3D TransformsCSS TransitionsCSS AnimationsCSS TooltipsCSS Style ImagesCSS Image ReflectionCSS object-fitCSS object-positionCSS ButtonsCSS PaginationCSS Multiple ColumnsCSS User InterfaceCSS Variables
The var() Function
Overriding Variables
Variables and JavaScript
Variables in Media Queries

CSS Box SizingCSS Media QueriesCSS MQ ExamplesCSS Flexbox
CSS Flexbox
CSS Flex Container
CSS Flex Items
CSS Flex Responsive

CSS Reference

CSS ReferenceCSS Browser SupportCSS SelectorsCSS FunctionsCSS Reference AuralCSS Web Safe FontsCSS Font FallbacksCSS AnimatableCSS UnitsCSS PX-EM ConverterCSS ColorsCSS Color ValuesCSS Default ValuesCSS Entities

CSS Properties

align-content
align-items
align-self
all
animation
animation-delay
animation-direction
animation-duration
animation-fill-mode
animation-iteration-count
animation-name
animation-play-state
animation-timing-function

backface-visibility
background
background-attachment
background-blend-mode
background-clip
background-color
background-image
background-origin
background-position
background-repeat
background-size
border
border-bottom
border-bottom-color
border-bottom-left-radius
border-bottom-right-radius
border-bottom-style
border-bottom-width
border-collapse
border-color
border-image
border-image-outset
border-image-repeat
border-image-slice
border-image-source
border-image-width
border-left
border-left-color
border-left-style
border-left-width
border-radius
border-right
border-right-color
border-right-style
border-right-width
border-spacing
border-style
border-top
border-top-color
border-top-left-radius
border-top-right-radius
border-top-style
border-top-width
border-width
bottom
box-decoration-break
box-shadow
box-sizing
break-after
break-before
break-inside

caption-side
caret-color
@charset
clear
clip
clip-path
color
column-count
column-fill
column-gap
column-rule
column-rule-color
column-rule-style
column-rule-width
column-span
column-width
columns
content
counter-increment
counter-reset
cursor

direction
display
empty-cells
filter
flex
flex-basis
flex-direction
flex-flow
flex-grow
flex-shrink
flex-wrap
float
font
@font-face
font-family
font-feature-settings
font-kerning
font-size
font-size-adjust
font-stretch
font-style
font-variant
font-variant-caps
font-weight

gap
grid
grid-area
grid-auto-columns
grid-auto-flow
grid-auto-rows
grid-column
grid-column-end
grid-column-gap
grid-column-start
grid-gap
grid-row
grid-row-end
grid-row-gap
grid-row-start
grid-template
grid-template-areas
grid-template-columns
grid-template-rows

hanging-punctuation
height
hyphens
@import
isolation
justify-content
@keyframes
left
letter-spacing

line-height
list-style
list-style-image
list-style-position
list-style-type

margin
margin-bottom
margin-left
margin-right
margin-top
max-height
max-width
@media
min-height
min-width
mix-blend-mode

object-fit
object-position
opacity
order
outline
outline-color
outline-offset
outline-style
outline-width
overflow
overflow-x
overflow-y

padding
padding-bottom
padding-left
padding-right
padding-top
page-break-after
page-break-before
page-break-inside
perspective
perspective-origin
pointer-events
position
quotes

resize
right
row-gap

scroll-behavior

tab-size
table-layout
text-align
text-align-last
text-decoration
text-decoration-color
text-decoration-line
text-decoration-style
text-indent
text-justify
text-overflow
text-shadow
text-transform
top

transform
transform-origin
transform-style
transition
transition-delay
transition-duration
transition-property
transition-timing-function

unicode-bidi
user-select

vertical-align
visibility

white-space
width
word-break
word-spacing
word-wrap
writing-mode

z-index

CSS Syntax

@media not|only mediatype and (mediafeature and|or|not
mediafeature)
{  CSS-Code;}

meaning of the not, only and and keywords:

not: The not keyword inverts the meaning of an entire media
query.

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

and: The and keyword combines a media feature with a media
type or other media features.

They are all optional. However, if you use not or
only, you must also specify a media type.

You can also have different stylesheets for different media, like
this:

<link rel=»stylesheet» media=»screen and (min-width:
900px)» href=»widescreen.css»><link rel=»stylesheet» media=»screen and (max-width:
600px)» href=»smallscreen.css»>….

CSS Advanced

CSS Rounded CornersCSS Border ImagesCSS BackgroundsCSS ColorsCSS Color KeywordsCSS Gradients
Linear Gradients
Radial Gradients

CSS Shadows
Shadow Effects
Box Shadow

CSS Text EffectsCSS Web FontsCSS 2D TransformsCSS 3D TransformsCSS TransitionsCSS AnimationsCSS TooltipsCSS Style ImagesCSS Image ReflectionCSS object-fitCSS object-positionCSS ButtonsCSS PaginationCSS Multiple ColumnsCSS User InterfaceCSS Variables
The var() Function
Overriding Variables
Variables and JavaScript
Variables in Media Queries

CSS Box SizingCSS Media QueriesCSS MQ ExamplesCSS Flexbox
CSS Flexbox
CSS Flex Container
CSS Flex Items
CSS Flex Responsive

Syntax

The media query syntax is described in terms of the CSS2 grammar. As such,
rules not defined here are defined in CSS2. The
production defined below replaces the
production from CSS2.

media_query_list
 : S* * ]?
 ;
media_query
 : ? S* media_type S* *
 | expression *
 ;
media_type
 : IDENT
 ;
expression
 : '(' S* media_feature S* ? ')' S*
 ;
media_feature
 : IDENT
 ;

COMMENT tokens, as defined by CSS2, do not occur in the grammar (to keep
it readable), but any number of these tokens may appear anywhere between
other tokens.

The following new definitions are introduced:

L  l|\\0{0,4}(4c|6c)(\r\n|)?|\\l
Y  y|\\0{0,4}(59|79)(\r\n|)?|\\y

The following new tokens are introduced:

{O}{N}{L}{Y}      {return ONLY;}
{N}{O}{T}         {return NOT;}
{A}{N}{D}         {return AND;}
{num}{D}{P}{I}    {return RESOLUTION;}
{num}{D}{P}{C}{M} {return RESOLUTION;}

is to be added to the CSS2
production.

CSS style sheets are generally case-insensitive, and this is also the
case for media queries.

In addition to conforming to the syntax, each media query needs to use
media types and media features according to their respective specification
in order to be considered conforming.

Only the first media query is conforming in the example below because
the «example» media type does not exist.

3.1. Error Handling

For media queries that are not conforming user agents need to follow the
rules described in this section.

  • Unknown media types. Unknown media types evaluate to
    false. Effectively, they are treated identically to known media types
    that do not match the media type of the device.

    The media query «» will evaluate to false, unless
    is actually a supported media type. Similarly,
    «» will evaluate to true.

    Unknown media types are distinct from media types that do
    not actually match the IDENT production. Those fall under the malformed
    media query clause.

  • Unknown media features. User agents are to represent
    a media query as «» when one of the specified media
    features is not known.

    In this example, the first media query will be represented as
    «» and evaluate to false and the second media query
    is evaluated as if the first had not been specified, effectively.

    Is represented as «» because the ‘’ feature does not accept the
    ‘’ prefix.

  • Unknown media feature values. As with unknown media
    features, user agents are to represent a media query as «» when one of the specified media feature values is not known.

    The media query specifies an unknown
    value for the ‘’ media feature
    and is therefore represented as «».

    This media query is represented as «» because
    negative lengths are not allowed for the ‘’ media feature:

  • Malformed media query. User agents are to handle
    unexpected tokens encountered while parsing a media query by reading
    until the end of the media query, while observing of (), [], {}, «», and », and correctly
    handling escapes. Media queries with unexpected tokens are represented
    as «».

    The following is an malformed media query because having no space
    between ‘’ and the expression is
    not allowed. (That is reserved for the functional notation syntax.)

    Media queries are expected to follow the error handling rules of the
    host language as well.

    … will not apply because the semicolon terminates the
    rule in CSS.

References

Normative references

Bert Bos; et al. Cascading Style
Sheets Level 2 Revision 1 (CSS 2.1) Specification.
7 June
2011. W3C Recommendation. URL: http://www.w3.org/TR/2011/REC-CSS2-20110607

Other references

Dave Raggett; Arnaud Le Hors; Ian Jacobs. HTML 4.01
Specification.
24 December 1999. W3C Recommendation. URL: http://www.w3.org/TR/1999/REC-html401-19991224
Ian Hickson. HTML5.
29 March 2012. W3C Working Draft. (Work in progress.) URL: http://www.w3.org/TR/2012/WD-html5-20120329/
G. Klyne; L. McIntyre. Content Feature Schema
for Internet Fax.
March 1999. Internet RFC 2531. URL: http://www.ietf.org/rfc/rfc2531.txt
James Clark; Simon Pieters; Henry S. Thompson Associating Style Sheets
with XML documents 1.0 (Second Edition)
28 October 2010. W3C
Recommendation. URL: http://www.w3.org/TR/2010/REC-xml-stylesheet-20101028/
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