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:
body { background-color: lightblue;}
Try it Yourself »
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 <h1>, <p>, and <div> elements will have different background colors:
h1 { background-color: green;}
div { background-color: lightblue;}p { background-color:
yellow;}
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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:
opacity 1
opacity 0.6
opacity 0.3
opacity 0.1
Example
div { background-color: green; opacity: 0.3;}
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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:
100% opacity
60% opacity
30% opacity
10% opacity
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
div { background: rgba(0, 128, 0, 0.3) /* Green background with 30% opacity */}
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The CSS Background Color Property
Property
Description
background-color
Sets the background color of an element
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Reference: https://www.w3schools.com/css/css_background.asp