How is stacking context formed?
A stacking context is created when an element is positioned and assigned a z-index value other than auto , or when an element has an opacity value less than 1. In WebKit and Chrome 22+ an element with a fixed position always creates a stacking context, even when the z-index value is auto .
What the heck is Z-index?
When we give an element a z-index, that value is only compared against other elements in the same context. z-index values are not global. By default, a plain HTML document will have a single stacking context that encompasses all nodes.
Will change stacking context?
In will change, setting will-change to a property whose any non-initial value would create a stacking context. In masking, setting clip-path / mask with a value other than none .
Why is Z-index important?
Z-index is a CSS property that allows you to position elements in layers on top of one another. It’s super useful, and honestly a very important tool to know how to use in CSS. Unfortunately, z-index is one of those properties that doesn’t always behave in an intuitive way.
What is a stacking context?
The stacking context is a three-dimensional conceptualization of HTML elements along an imaginary z-axis relative to the user, who is assumed to be facing the viewport or the webpage. HTML elements occupy this space in priority order based on element attributes.
How do I make a div in front of everything?
Use the CSS z-index property. Elements with a greater z-index value are positioned in front of elements with smaller z-index values. Note that for this to work, you also need to set a position style ( position:absolute , position:relative , or position:fixed ) on both/all of the elements you want to order.
What is a stacking order?
(graphics) The relationship between windows that (partially) obscure each other. A window manager will include commands to alter the stacking order by bringing a chosen window to the front (top) or back (bottom) of the stack.
Can I use negative Z-index?
z-index: -1; You can use negative values. The target element is move in behind its siblings.
What is the highest Z-index?
2147483647
The maximum range is ±2147483647. In CSS code bases, you’ll often see z-index values of 999, 9999 or 99999. This is a perhaps lazy way to ensure that the element is always on top. It can lead to problems down the road when multiple elements need to be on top.
Does position relative create a stacking context?
A stacking context is formed, anywhere in the document, by any element in the following scenarios: Root element of the document ( ). Element with a position value absolute or relative and z-index value other than auto .