How to do css backgrounds

CSS background Property

Set different background properties in one declaration:

Definition and Usage

The background property is a shorthand property for:

It does not matter if one of the values above are missing, e.g. background:#ff0000 url(smiley.gif); is allowed.

Default value:	see individual properties
Inherited:	no
Animatable:	yes, see individual properties. Read about animatable Try it
Version:	CSS1 + new properties in CSS3
JavaScript syntax:	object.style.background=»red url(smiley.gif) top left no-repeat» Try it

Browser Support

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

Note: See individual browser support for each value below.

CSS Syntax

background: bg-color bg-image position/bg-size bg-repeat bg-origin bg-clip bg-attachment initial|inherit;

Note: If one of the properties in the shorthand declaration is the bg-size property, you must use a / (slash) to separate it from the bg-position property, e.g. background:url(smiley.gif) 10px 20px/50px 50px; will result in a background image, positioned 10 pixels from the left, 20 pixels from the top, and the size of the image will be 50 pixels wide and 50 pixels high.

Note: If using multiple background-image sources but also want a background-color, the background-color parameter needs to be last in the list.

Property Values

Value	Description	CSS	Demo
background-color	Specifies the background color to be used	1	Demo ❯
background-image	Specifies ONE or MORE background images to be used	1	Demo ❯
background-position	Specifies the position of the background images	1	Demo ❯
background-size	Specifies the size of the background images	3	Demo ❯
background-repeat	Specifies how to repeat the background images	1	Demo ❯
background-origin	Specifies the positioning area of the background images	3	Demo ❯
background-clip	Specifies the painting area of the background images	3	Demo ❯
background-attachment	Specifies whether the background images are fixed or scrolls with the rest of the page	1
initial	Sets this property to its default value. Read about initial	3
inherit	Inherits this property from its parent element. Read about inherit	2

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CSS Backgrounds

The CSS background properties are used to add background effects for elements.

In these chapters, you will learn about the following CSS background properties:

• background-color
• background-image
• background-repeat
• background-attachment
• background-position
• background (shorthand property)

CSS background-color

The background-color property specifies the background color of an element.

Example

The background color of a page is set like this:

With CSS, a color is most often specified by:

• a valid color name — like «red»
• a HEX value — like «#ff0000»
• an RGB value — like «rgb(255,0,0)»

Look at CSS Color Values for a complete list of possible color values.

Other Elements

You can set the background color for any HTML elements:

Example

Here, the ,

, and elements will have different background colors:

div background-color: lightblue;
>

Opacity / Transparency

The opacity property specifies the opacity/transparency of an element. It can take a value from 0.0 — 1.0. The lower value, the more transparent:

Example

Note: When using the opacity property to add transparency to the background of an element, all of its child elements inherit the same transparency. This can make the text inside a fully transparent element hard to read.

Transparency using RGBA

If you do not want to apply opacity to child elements, like in our example above, use RGBA color values. The following example sets the opacity for the background color and not the text:

You learned from our CSS Colors Chapter, that you can use RGB as a color value. In addition to RGB, you can use an RGB color value with an alpha channel (RGBA) — which specifies the opacity for a color.

An RGBA color value is specified with: rgba(red, green, blue, alpha). The alpha parameter is a number between 0.0 (fully transparent) and 1.0 (fully opaque).

Tip: You will learn more about RGBA Colors in our CSS Colors Chapter.

Example

The CSS Background Color Property

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CSS Multiple Backgrounds

In this chapter you will learn how to add multiple background images to one element.

You will also learn about the following properties:

CSS Multiple Backgrounds

CSS allows you to add multiple background images for an element, through the background-image property.

The different background images are separated by commas, and the images are stacked on top of each other, where the first image is closest to the viewer.

The following example has two background images, the first image is a flower (aligned to the bottom and right) and the second image is a paper background (aligned to the top-left corner):

Example

#example1 <
background-image: url(img_flwr.gif), url(paper.gif);
background-position: right bottom, left top;
background-repeat: no-repeat, repeat;
>

Multiple background images can be specified using either the individual background properties (as above) or the background shorthand property.

The following example uses the background shorthand property (same result as example above):

Example

CSS Background Size

The CSS background-size property allows you to specify the size of background images.

The size can be specified in lengths, percentages, or by using one of the two keywords: contain or cover.

The following example resizes a background image to much smaller than the original image (using pixels):

Lorem Ipsum Dolor

Lorem ipsum dolor sit amet, consectetuer adipiscing elit, sed diam nonummy nibh euismod tincidunt ut laoreet dolore magna aliquam erat volutpat.

Ut wisi enim ad minim veniam, quis nostrud exerci tation ullamcorper suscipit lobortis nisl ut aliquip ex ea commodo consequat.

Example

The two other possible values for background-size are contain and cover .

The contain keyword scales the background image to be as large as possible (but both its width and its height must fit inside the content area). As such, depending on the proportions of the background image and the background positioning area, there may be some areas of the background which are not covered by the background image.

The cover keyword scales the background image so that the content area is completely covered by the background image (both its width and height are equal to or exceed the content area). As such, some parts of the background image may not be visible in the background positioning area.

The following example illustrates the use of contain and cover :

Example

#div1 <
background: url(img_flower.jpg);
background-size: contain;
background-repeat: no-repeat;
>

#div2 background: url(img_flower.jpg);
background-size: cover;
background-repeat: no-repeat;
>

Define Sizes of Multiple Background Images

The background-size property also accepts multiple values for background size (using a comma-separated list), when working with multiple backgrounds.

The following example has three background images specified, with different background-size value for each image:

Example

#example1 <
background: url(img_tree.gif) left top no-repeat, url(img_flwr.gif) right bottom no-repeat, url(paper.gif) left top repeat;
background-size: 50px, 130px, auto;
>

Full Size Background Image

Now we want to have a background image on a website that covers the entire browser window at all times.

The requirements are as follows:

• Fill the entire page with the image (no white space)
• Scale image as needed
• Center image on page
• Do not cause scrollbars

The following example shows how to do it; Use the element (the element is always at least the height of the browser window). Then set a fixed and centered background on it. Then adjust its size with the background-size property:

Example

Hero Image

You could also use different background properties on a to create a hero image (a large image with text), and place it where you want.

Example

.hero-image <
background: url(img_man.jpg) no-repeat center;
background-size: cover;
height: 500px;
position: relative;
>

CSS background-origin Property

The CSS background-origin property specifies where the background image is positioned.

The property takes three different values:

• border-box — the background image starts from the upper left corner of the border
• padding-box — (default) the background image starts from the upper left corner of the padding edge
• content-box — the background image starts from the upper left corner of the content

The following example illustrates the background-origin property:

Example

#example1 <
border: 10px solid black;
padding: 35px;
background: url(img_flwr.gif);
background-repeat: no-repeat;
background-origin: content-box;
>

CSS background-clip Property

The CSS background-clip property specifies the painting area of the background.

The property takes three different values:

• border-box — (default) the background is painted to the outside edge of the border
• padding-box — the background is painted to the outside edge of the padding
• content-box — the background is painted within the content box

The following example illustrates the background-clip property:

Example

#example1 <
border: 10px dotted black;
padding: 35px;
background: yellow;
background-clip: content-box;
>

CSS Advanced Background Properties

Property	Description
background	A shorthand property for setting all the background properties in one declaration
background-clip	Specifies the painting area of the background
background-image	Specifies one or more background images for an element
background-origin	Specifies where the background image(s) is/are positioned
background-size	Specifies the size of the background image(s)

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