How to set background transparency in css-CSS Tutorial-php.cn

How to set background transparency in css

王林

Release： 2020-08-29 16:06:44

forward

3270 people have browsed it

How to set background transparency in css

There are many ways to achieve background transparency. This article introduces the following two methods:

(recommended related tutorials: CSS Tutorial）

css3’s opacity:x, the value of x is from 0 to 1, such as opacity: 0.8

css3’s rgba(red, green, blue, alpha), the value of alpha From 0 to 1, such as rgba(255,255,255,0.8)

1. Opacity of css3

Compatibility: IE6, 7, and 8 are not supported, but IE9 and above are supported by standard browsers

Instructions for use: All descendant elements of the opacity element will be set to be transparent together. It is generally used to adjust the overall opacity of the image or module.

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>背景透明度</title>
<style>
.demo{
  padding: 25px;
  background-color:#000000;
  filter:alpha(opacity:50); opacity:0.5;  -moz-opacity:0.5;-khtml-opacity: 0.5;
}
.demo p{
    color: #FFFFFF;
}
</style>
</head>
<body>    
 
<div class="demo">
    <p>背景透明，文字也透明</p>
</div>
</body>
</html>

Copy after login

After using opacity, the entire module will be transparent. , shown as follows:

How to set background transparency in css

# Then it is not advisable to use opacity to achieve "transparent background, opaque text".

(Video tutorial recommendation: css video tutorial)

2. Rgba of css3

The so-called RGBA color, as the name means, is the color of R G B A, and then Specifically, it is the color of red green blue alpha, which translates into the transparent color of red green blue alpha.

background:rgba(200, 54, 54, 0.5);

Copy after login

Among them, the 0 in front of 0.5 indicating translucency can be omitted, or directly .5 is also acceptable.

Compatibility: IE6, 7, and 8 are not supported, IE9 and above and standard browsers are supported

How to solve the problem that IE8 browser does not support rgba:

background:rgba(0,0,0,0.5); filter: progid:DXImageTransform.Microsoft.gradient(startcolorstr=#7F000000,endcolorstr=#7F000000);

Copy after login

Instructions for use: Set the opacity of the color, generally used to adjust the opacity of background-color, color, box-shadow, etc.

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>css3的rgba</title>
<style>
.demo{
  padding: 25px;
  background-color:#000000;/* IE6和部分IE7内核的浏览器(如QQ浏览器)下颜色被覆盖 */
  background-color:rgba(0,0,0,0.2); /* IE6和部分IE7内核的浏览器(如QQ浏览器)会读懂，但解析为透明 */
}
.demo p{
    color: #FFFFFF;
}
</style>
</head>
<body>    
<div class="demo">
    <p>背景透明，文字也透明</p>
</div>
</body>
</html>

Copy after login

Use rgba in background-color. In standard browsers, the background is transparent and the text is opaque, as shown below:

How to set background transparency in css

## Then use rgba to achieve background transparency , text opacity is desirable.

The above is the detailed content of How to set background transparency in css. For more information, please follow other related articles on the PHP Chinese website!