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Overview
The CSS background properties are used to add background effects for elements. In these chapters, you will learn about the following CSS background properties:
Formula
background - color background - image background - repeat background - attachment background - position background(shorthand property)
Formula
The background - color property specifies the background color of an element.The background color of a page is set like this:
body {
background-color: lightblue;
}With CSS, a color is most often specified by:
Formula
a valid color name - like "red"
a HEX value - like "#ff0000"
an RGB value - like "rgb(255,0,0)"CSS Color Values for a complete list of possible color values.
You can set the background color for any HTML elements:
Formula
Here, the < h1 >, < p >, and < div > elements will have different background colors:h1 {
background-color: green;
}
div {
background-color: lightblue;
}
p {Formula
background - color:yellow;
}Formula
Opacity / TransparencyThe 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;
}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.
If you do not want to apply opacity to child elements, like in our example above, use
color values. The following example sets the opacity for the background color and not the text: 100% opacity 60% opacity 30% opacity 10% opacity
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 (RGB A
Formula
) - 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).
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 */
}