overscroll-behavior-block

The overscroll-behavior-block CSS property sets the browser's behavior when the block direction boundary of a scrolling area is reached.

See overscroll-behavior for a full explanation.

/* Keyword values */
overscroll-behavior-block: auto; /* default */
overscroll-behavior-block: contain;
overscroll-behavior-block: none;

/* Global values */
overscroll-behavior-block: inherit;
overscroll-behavior-block: initial;
overscroll-behavior-block: revert;
overscroll-behavior-block: unset;

Syntax

The overscroll-behavior-block property is specified as a keyword chosen from the list of values below.

Values

auto

The default scroll overflow behavior occurs as normal.

contain

Default scroll overflow behavior is observed inside the element this value is set on (e.g. "bounce" effects or refreshes), but no scroll chaining occurs to neighboring scrolling areas, e.g. underlying elements will not scroll.

none

No scroll chaining occurs to neighboring scrolling areas, and default scroll overflow behavior is prevented.

Formal definition

Initial valueauto
Applies tonon-replaced block-level elements and non-replaced inline-block elements
Inheritedno
Computed valueas specified
Animation typediscrete

Formal syntax

contain | none | auto

Examples

Preventing block overscrolling

In this demo we have two block-level boxes, one inside the other. The outer box has a large height set on it so the page will scroll vertically. The inner box has a small width (and height) set on it so it sits comfortably inside the viewport, but its content is given a large height so it will also scroll vertically.

By default, when the inner box is scrolled and a scroll boundary is reached, the whole page will begin to scroll, which is probably not what we want. To avoid this happening in the block direction, we've set overscroll-behavior-block: contain on the inner box.

HTML

<main>
  <div>
    <div>
      <p><code>overscroll-behavior-block</code> has been used to make it so that when the scroll boundaries of the yellow inner box are reached, the whole page does not begin to scroll.</p>
    </div>
  </div>
</main>

CSS

main {
  height: 3000px;
  width: 500px;
  background-color: white;
  background-image: repeating-linear-gradient(to bottom, rgba(0,0,0,0) 0px, rgba(0,0,0,0) 19px, rgba(0,0,0,0.5) 20px);
}

main > div {
  height: 300px;
  width: 400px;
  overflow: auto;
  position: relative;
  top: 50px;
  left: 50px;
  overscroll-behavior-block: contain;
}

div > div {
  height: 1500px;
  width: 100%;
  background-color: yellow;
  background-image: repeating-linear-gradient(to bottom, rgba(0,0,0,0) 0px, rgba(0,0,0,0) 19px, rgba(0,0,0,0.5) 20px);
}

p {
  padding: 10px;
  background-color: rgba(255,0,0,0.5);
  margin: 0;
  width: 340px;
  position: relative;
  top: 10px;
  left: 10px;
}

Result

Specifications

Specification
CSS Overscroll Behavior Module Level 1
# overscroll-behavior-longhands-logical

Browser compatibility

BCD tables only load in the browser

See also