How Does Absolute Positioning Work When Nested Within Another Absolutely Positioned Element?

Absolute Positioning within Absolute Positioning

When working with web page layouts, it's common to use positioning techniques like absolute positioning to arrange elements precisely within a page. However, a potential issue arises when you attempt to apply absolute positioning within an element that itself is absolutely positioned.

Suppose you have a container element (1st div) with relative positioning (position:relative), which allows you to position child elements relative to its own position. Within this container, you have an absolutely positioned element (2nd div) and a third absolutely positioned element (3rd div) nested within the 2nd div.

In this scenario, you might expect the 3rd div to be positioned absolutely relative to the 1st div, even though the 2nd div is also absolutely positioned. However, this is not the case.

Understanding the Positioning Hierarchy

The reason for this behavior lies in the way absolute positioning works. When an element is given absolute positioning, it is removed from the normal flow of the document and instead positioned relative to its nearest positioned ancestor. In this case, the 2nd div is the nearest positioned ancestor of the 3rd div, regardless of whether the 1st div also has relative positioning.

This means that the absolute position of the 3rd div is calculated relative to the 2nd div's position, not the 1st div's position. As a result, the 3rd div will appear absolutely positioned within the 2nd div, not the 1st div.

Alternate Positioning Technique

If you want the 3rd div to be absolutely positioned relative to the 1st div, you need to make it a direct child of the 1st div. This will allow the 3rd div to inherit the absolute position of the 1st div and be positioned accordingly.

It's important to note that position: absolute resets the relative position for children just as position: relative does. Therefore, if you have multiple absolutely positioned child elements within a relatively positioned parent element, their positions will be calculated independently, relative to their nearest absolutely positioned ancestor.

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