About css media queries

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.

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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Responsive Web Design — Media Queries

It uses the @media rule to include a block of CSS properties only if a certain condition is true.

Example

If the browser window is 600px or smaller, the background color will be lightblue:

Add a Breakpoint

Earlier in this tutorial we made a web page with rows and columns, and it was responsive, but it did not look good on a small screen.

Media queries can help with that. We can add a breakpoint where certain parts of the design will behave differently on each side of the breakpoint.

Desktop

Phone

Use a media query to add a breakpoint at 768px:

Example

When the screen (browser window) gets smaller than 768px, each column should have a width of 100%:

@media only screen and (max-width: 768px) /* For mobile phones: */
[class*=»col-«] width: 100%;
>
>

Always Design for Mobile First

Mobile First means designing for mobile before designing for desktop or any other device (This will make the page display faster on smaller devices).

This means that we must make some changes in our CSS.

Instead of changing styles when the width gets smaller than 768px, we should change the design when the width gets larger than 768px. This will make our design Mobile First:

Example

/* For mobile phones: */
[class*=»col-«] width: 100%;
>

Another Breakpoint

You can add as many breakpoints as you like.

We will also insert a breakpoint between tablets and mobile phones.

Desktop

Tablet

Phone

We do this by adding one more media query (at 600px), and a set of new classes for devices larger than 600px (but smaller than 768px):

Example

Note that the two sets of classes are almost identical, the only difference is the name ( col- and col-s- ):

/* For mobile phones: */
[class*=»col-«] width: 100%;
>

It might seem odd that we have two sets of identical classes, but it gives us the opportunity in HTML, to decide what will happen with the columns at each breakpoint:

HTML Example

For desktop:

The first and the third section will both span 3 columns each. The middle section will span 6 columns.

For tablets:

The first section will span 3 columns, the second will span 9, and the third section will be displayed below the first two sections, and it will span 12 columns:

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

/* 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)

Orientation: Portrait / Landscape

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:

Example

The web page will have a lightblue background if the orientation is in landscape mode:

Hide Elements With Media Queries

Another common use of media queries, is to hide elements on different screen sizes:

Example

/* If the screen size is 600px wide or less, hide the element */
@media only screen and (max-width: 600px) div.example display: none;
>
>

Change Font Size With Media Queries

You can also use media queries to change the font size of an element on different screen sizes:

Variable Font Size.

Example

/* If the screen size is 601px or more, set the font-size of

/* If the screen size is 600px or less, set the font-size of to 30px */
@media only screen and (max-width: 600px) div.example font-size: 30px;
>
>

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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