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目录

CSS background-size Property

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Example

Specify the size of a background-image with "auto" and in pixels:

#example1 {
  background: url(mountain.jpg);
  background-repeat: no-repeat;
  background-size: auto;
}

#example2 {
  background: url(mountain.jpg);
  background-repeat: no-repeat;
  background-size: 300px 100px;
}
Try it Yourself »

More "Try it Yourself" examples below.

Definition and Usage

The background-size property specifies the size of the background images.

There are four different syntaxes you can use with this property: the keyword syntax ("auto", "cover" and "contain"), the one-value syntax (sets the width of the image (height becomes "auto"), the two-value syntax (first value: width of the image, second value: height), and the multiple background syntax (separated with comma).

Show demo ❯

Default value: auto
Inherited: no
Animatable: yes. Read about animatable Try it
Version: CSS3
JavaScript syntax: object.style.backgroundSize="60px 120px" Try it

Browser Support

The numbers in the table specify the first browser version that fully supports the property.

Numbers followed by -webkit-, -moz-, or -o- specify the first version that worked with a prefix.

Property
background-size  4.0
1.0 -webkit-		 9.0 4.0
3.6 -moz-		 4.1
3.0 -webkit-		 10.5
10.0 -o-

CSS Syntax

background-size: auto| length|cover|contain|initial|inherit;

Property Values

Value Description Demo
auto Default value. The background image is displayed in its original size Demo ❯
length Sets the width and height of the background image. The first value sets the width, the second value sets the height. If only one value is given, the second is set to "auto". Read about length units Demo ❯
percentage Sets the width and height of the background image in percent of the parent element. The first value sets the width, the second value sets the height. If only one value is given, the second is set to "auto" Demo ❯
cover Resize the background image to cover the entire container, even if it has to stretch the image or cut a little bit off one of the edges Demo ❯
contain Resize the background image to make sure the image is fully visible Demo ❯
initial Sets this property to its default value. Read about initial
inherit Inherits this property from its parent element. Read about inherit

More Examples

Example

Specify the size of a background image with percent:

#example1 {
  background: url(mountain.jpg);
  background-repeat: no-repeat;
  background-size: 100% 100%;
}

#example2 {
  background: url(mountain.jpg);
  background-repeat: no-repeat;
  background-size: 75% 50%;
}
Try it Yourself »

Example

Specify the size of a background image with "cover":

#example1 {
  background: url(mountain.jpg);
  background-repeat: no-repeat;
  background-size: cover;
}
Try it Yourself »

Example

Specify the size of a background image with "contain":

#example1 {
  background: url(mountain.jpg);
  background-repeat: no-repeat;
  background-size: contain;
}
Try it Yourself »

Example

Here we have two background images. We specify the size of the first background image with "contain", and the second background-image with "cover":

#example1 {
  background: url(img_tree.gif), url(mountain.jpg);
  background-repeat: no-repeat;
  background-size: contain, cover;
}
Try it Yourself »

Example

Use different background properties to create a "hero" image:

.hero-image {
  background-image: url("photographer.jpg"); /* The image used */
  background-color: #cccccc; /* Used if the image is unavailable */
  height: 500px; /* You must set a specified height */
  background-position: center; /* Center the image */
  background-repeat: no-repeat; /* Do not repeat the image */
  background-size: cover; /* Resize the background image to cover the entire container */
}
Try it Yourself »

Related Pages

CSS tutorial: CSS Backgrounds

HTML DOM reference: backgroundSize property


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