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CSS z-index Property

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Definition

The z-index property sets the stack order of an element. An element with greater stack order is always in front of another element with lower stack order.

Note: Elements can have negative stack orders.

Note: Z-index only works on elements that have been positioned (eg position:absolute;)!

Inherited: No

JavaScript Syntax

CSS properties can also be dynamically changed with a JavaScript.

Scripting Syntax: object.style.zIndex="1"

In our HTML DOM tutorial you can find more details about the zIndex property.

In our HTML DOM tutorial you can also find a full Style Object Reference.

Example

img
{ 
z-index: -1
}  

Possible Values

Value Description
auto Default. The stack order is equal to its parents 
number Sets the stack order of the element

Try-It-Yourself Demos

Z-index
Z-index can be used to place an element "behind" another element.

Z-index
The elements in the example above have now changed their Z-index.

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