Container queries

With media queries you can adjust layouts based on the size of the viewport or the type of device being used. Container queries allow you to make more specific adjustments to elements based on the size and state of their ancestors, or containers.

Imagine you have a newsletter sign-up form that is meant to be used in several contexts on your site. You might want it to span the full width of the page on a signup page, but go into a split column on a page with other content.

As shown in this demo, with container queries you can adjust the properties such as font-size, padding, and the layout of the element based on attributes of its nearest container, independent of the viewport size.

Setting up a container query

Unlike media queries, container queries are established in two parts:

1. Define a container.
2. Write styles for a child element to be applied when a parent container matches the query's conditions.

Defining a container

You can define a container by using the container-type property.

.my-container-element {   container-type: inline-size; } 

A container-type of inline-size lets you query the container's inline axis.

To query against both the inline and block axes, use container-type: size.

main, .my-component {   container-type: size; } 

Both values of container-type apply different types of size containment. Inline-size containment on an element prevents its descendants from affecting its inline-size.

An element with size containment prevents its descendants from affecting its size in both the block and inline axes.

In this example you can see size containment can affect the element on which it is applied.

Since it won't be sized based on the size of its children (the <p> element), the container will collapse unless given an explicit size by setting its dimensions (that is, inline-size, block-size, aspect-ratio) or placing it into an explicitly sized layout.

Container query conditions

Once a container is established, you can add a condition, wrapped in parentheses, that must be true for the styles inside of the container query to be applied. For container size queries, which are based on the dimensions of ancestor elements, the condition is made up of the following:

• a size feature: width, height, inline-size, block-size, aspect-ratio, or orientation,
• a comparison operator (that is, >, <, =, >=),
• and a length value.

.my-container-element {   container-type: inline-size; }  @container (inline-size > 30em) {   .my-child-element {     /* styles to apply when .my-container-element is wider than 30em */   } } 

Size feature conditions can also be written with a colon and a single value to test.

@container (orientation: landscape) {   /*...*/ }  @container (min-width: 300px) {   /*...*/ } 

You can also combine multiple conditions by using keywords like and and or, or chaining multiple conditions together with operators.

@container (inline-size > 40em) and (orientation: landscape)  {   /*...*/ }  @container (height > 25vh) or (orientation: portrait) {   /*...*/ }  @container ( 10em <= width <= 500px) {   /*...*/ } 

Naming containers

To target specific containers, even if they are not the nearest ancestor, you can name containers with the container-name property. Then you can reference the container name you want to query before defining your conditions.

.sidebar {   container-name: main-sidebar;   container-type: inline-size; }  @container main-sidebar (inline-size > 20em)  {   .button-group {     display: flex;     padding-inline: 1.25em;   } } 

The named container must still be an ancestor of the elements being styled.

Use shorthand with the container property

The container property lets you use a shorthand syntax to both define a container and specify the container type.

.sidebar {   container: main-sidebar / inline-size; } 

The name of the container comes before the slash and the type of container comes after.

Container query units

Within containers you also have access to container relative length units. This provides more flexibility for components that can exist in different containers, since the relative lengths will adjust depending on the dimensions of the container.

Here the container length unit cqi (1% of a query container's inline size) is being used for the button's padding.

.container {   container: button-container / inline-size; }  .one {   inline-size: 30vw; }  .two {   inline-size: 50vw; }  button {   padding: 2cqi 5cqi; } 

Both buttons have the same relative units applied, but since the units are relative to the container's size, the second button has more padding due to its larger container.

Nesting container queries

You can nest container queries inside of selectors.

.my-element {   display: grid;   padding: 1em 2em;    @container my-container (min-inline-size: 22em) {     /* styles to apply when element's container is wider than 22em */   } }  /* equivalent to */ .my-element {   display: grid;   padding: 1em 2em; }  @container my-container (min-inline-size: 22em) {   .my-element {      /* styles to apply when element's is wider than 22em */   } } 

Or nest them inside of other container queries or at-rules.

@container my-container (min-inline-size: 22em) {   .my-element {       /* styles to apply when element's is wider than 22em */   } } 

@layer base {   @container my-container (min-inline-size: 22em) {     .my-element {     /* styles to apply */     }   } } 

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