freeCodeCamp/guide/chinese/css/image-opacity-and-transparency/index.md

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---
title: Image Opacity and Transparency
localeTitle: 图像不透明度和透明度
---
## 图像不透明度和透明度
`opacity`属性允许您通过降低图像的`opacity`来使图像透明。
`Opacity`的值介于0.0和1.0之间。
1.0是任何图像的默认值。它是完全不透明的。
```css
img {
opacity: 0.3;
}
```
Include ```filter: alpha(opacity=x)``` for IE8 and earlier. The x takes a value from 0-100.
```
CSS img { 不透明度0.3; filteralphaopacity = 30; }
```
Here's an example of an image set to the parameters in the example above.
![image at 30% opacity](https://github.com/lvcoulter/images/blob/master/Opacity30percent.jpg?raw=true)
You can pair ```opacity``` with ```:hover``` to create a dynamic mouse-over effect.
Example:
```
CSS img { 不透明度0.3; filteralphaopacity = 30; } imghover { 不透明度1.0; filteralphaopacity = 100; }
```
[A codepen example to show a transparent image turning opaque on hover](https://codepen.io/lvcoulter/full/JrzxXa/)
<!--I cannot figure out how to embed a Codepen. I would really like to know-->
You can create the opposite effect with less code since the image is 1.0 opacity by default
Example:
```
CSS imghover { 不透明度0.3; filteralphaopacity = 30; } \`\`\` [用于显示鼠标悬停透明度的codepen示例](https://codepen.io/lvcoulter/full/xXBQoR/)
#### 更多信息:
\-w3schools.com [CSS不透明度/透明度](https://www.w3schools.com/css/css_image_transparency.asp)
\-MDN web docs [Opacity](https://developer.mozilla.org/en-US/docs/Web/CSS/opacity)