Example
Use z-index utilities to stack elements on top of one another. Requires a position value other than static, which can be set with custom styles or using our position utilities.
z-index utilities because of their default values of -1 through 3, which we use for the layout of overlapping components. High-level z-index values are used for overlay components like modals and tooltips.<div class="z-3 position-absolute p-5 rounded-3"><span>z-3</span></div>
<div class="z-2 position-absolute p-5 rounded-3"><span>z-2</span></div>
<div class="z-1 position-absolute p-5 rounded-3"><span>z-1</span></div>
<div class="z-0 position-absolute p-5 rounded-3"><span>z-0</span></div>
<div class="z-n1 position-absolute p-5 rounded-3"><span>z-n1</span></div>Overlays
Bootstrap overlay components—dropdown, modal, offcanvas, popover, toast, and tooltip—all have their own z-index values to ensure a usable experience with competing “layers” of an interface.
Read about them in the z-index layout page.
Component approach
On some components, we use our low-level z-index values to manage repeating elements that overlap one another (like buttons in a button group or items in a list group).
Learn about our z-index approach.
CSS
Sass maps
Customize this Sass map to change the available values and generated utilities.
$zindex-levels: (
n1: -1,
0: 0,
1: 1,
2: 2,
3: 3
);
Sass utilities API
Position utilities are declared in our utilities API in scss/_utilities.scss. Learn how to use the utilities API.
"z-index": (
property: z-index,
class: z,
values: $zindex-levels,
)