Why Doesn't My Sticky Bottom Element Stick?

Sticky Position and Its Behavior

When working with CSS positioning, the 'position: sticky;' property offers a unique behavior. It allows an element to remain fixed within its container until it reaches a certain threshold. One common misunderstanding involves the use of 'bottom: 0'.

The issue:

In the example code provided, a pink block contains a blue one with 'position: sticky; bottom: 0'. However, the blue block doesn't seem to stick to the bottom of its container.

The solution:

Surprisingly, the code is working correctly. The definition of CSS 'sticky' behavior explains:

"A stickily positioned element remains relatively positioned until its containing block crosses a specified threshold within its flow root."

In this case, the blue block becomes fixed only when the user scrolls the page until the pink block overlaps with the bottom of the viewport.

Experimental Demonstration:

To create a more evident effect, assign a large margin-top value to the pink block, and observe as you scroll slowly. The blue block will begin sticking to the bottom as the pink block reaches the bottom of the page's visible area.

By understanding how CSS 'sticky' functions, you can effectively use it to create more dynamic layouts that adjust and remain visible throughout the scrolling experience.

The above is the detailed content of Why Doesn't My Sticky Bottom Element Stick?. For more information, please follow other related articles on the PHP Chinese website!