Definition opacity
Подработка: Перевод страницы
The opacity property sets the opacity level for an element.
The opacity-level describes the transparency-level, where 1 is not transparent at all, 0.5 is 50% see-through, and 0 is completely transparent.
Note: When using the opacity property to add transparency to the background of an element, all of its child elements become transparent as well. This can make the text inside a fully transparent element hard to read. If you do not want to apply opacity to child elements, use RGBA color values instead (See "More Examples" below).
| Default value: | 1 |
|---|---|
| Inherited: | no |
| Animatable: | yes, see individual properties. Read about animatable Try it |
| Version: | CSS3 |
| JavaScript syntax: | object.style.opacity="0.5" Try it |
Browser Support opacity
The numbers in the table specify the first browser version that fully supports the property.
| Property | |||||
|---|---|---|---|---|---|
| opacity | 4.0 | 9.0 | 2.0 | 3.1 | 9.0 |
CSS Syntax opacity
opacity: number|initial|inherit;
Property Values opacity
| Value | Description | Demo |
|---|---|---|
| number | Specifies the opacity. From 0.0 (fully transparent) to 1.0 (fully opaque) | Demo ❯ |
| initial | Sets this property to its default value. Read about initial | |
| inherit | Inherits this property from its parent element. Read about inherit |
More Examples opacity
The opacity property adds transparency to the background of an element, and to all of its child elements as well. This makes the text inside a transparent element hard to read:
div.first {
opacity: 0.1;
}
div.second {
opacity: 0.3;
}
div.third {
opacity: 0.6;
}
Try it Yourself »
To not apply opacity to child elements (like in the example above) use RGBA color values instead. The following example sets the opacity for the background color, but not for the text:
div.first {
background: rgba(76, 175, 80, 0.1);
}
div.second {
background: rgba(76, 175, 80, 0.3);
}
div.third {
background: rgba(76, 175, 80,
0.6);
}
Try it Yourself »
Tip: Learn more about RGBA Colors in CSS RGBA Colors.
How to use JavaScript to change the opacity for an element:
function myFunction(x) {
// Return the text of the selected option
var opacity = x.options[x.selectedIndex].text;
var el = document.getElementById("p1");
if (el.style.opacity !== undefined) {
el.style.opacity = opacity;
} else {
alert("Your browser doesn't support this example!");
}
}
Try it Yourself »
Related Pages opacity
CSS Tutorial: CSS Opacity / Transparency
CSS Tutorial: CSS RGBA Colors
HTML DOM Reference: opacity property