The opacity property is used in the image to describes the transparency of the image. The value of opacity lies between 0.0 to 1.0 where the low value represents high transparent and high value represents low transparent. The percentage of opacity is calculated as Opacity% = Opacity * 100 To set the opacity only to the background and not the text inside it. It can be set by using the RGBA color values instead of the opacity property because using the opacity property can make the text inside it fully transparent element.
Syntax:
element {
background: rgba(red, green, blue, alpha);
// CSS property
}
Each parameter (red, green, and blue) defines the intensity of the color between 0 and 255. The RGBA color values are an extension of RGB color values with an alpha channel which specifies the opacity for a color. The alpha parameter is a number between 0.0 (fully transparent) and 1.0 (fully opaque).
Example:
html
<!DOCTYPE html>
<html>
<head>
<title>rgba property</title>
<style>
h1 {
color: green;
}
h1, h2 {
text-align: center;
}
div {
background: rgb(0, 151, 19);
padding: 10px;
text-align:justify;
}
div.first {
/*setting alpha = 0.1*/
background: rgba(0, 151, 19, 0.1);
}
div.second {
/*setting alpha = 0.3*/
background: rgba(0, 151, 19, 0.3);
}
div.third {
/*setting alpha = 0.6*/
background: rgba(0, 151, 19, 0.6);
}
</style>
</head>
<body>
<h1>GeeksforGeeks</h1>
<h2>Using RGBA color values:</h2>
<div class="first">
<p>This paragraph is shown at 10% opacity.</p>
</div>
<div class="second">
<p>This paragraph is shown at 30% opacity.</p>
</div>
<div class="third">
<p>This paragraph is shown at 60% opacity.</p>
</div>
<div>
<p>This is default.</p>
</div>
</body>
</html>
|
Output: 
CSS is the foundation of webpages and is used for webpage development by styling websites and web apps. You can learn CSS from the ground up by following this CSS Tutorial and CSS Examples.