Web/CSS/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: 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 neighbouring scrolling areas, e.g. underlying elements will not scroll.
none: No scroll chaining occurs to neighbouring scrolling areas, and default scroll overflow behavior is prevented.

Formal definition

Initial value	`auto`
Applies to	non-replaced block-level elements and non-replaced inline-block elements
Inherited	no
Computed value	as specified
Animation type	discrete

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 comforably 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	Status	Comment
CSS Overscroll Behavior Module Level 1The definition of 'overscroll-behavior-block' in that specification.	Working Draft

Browser compatibility

Update compatibility data on GitHub

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
`overscroll-behavior-block`	Chrome Full support 77	Edge Full support 79	Firefox Full support 73	IE No support No	Opera Full support 64	Safari No support No Notes' No support No Notes' Notes' See bug 176454.	WebView Android Full support 77	Chrome Android Full support 77	Firefox Android No support No	Opera Android Full support 55	Safari iOS No support No Notes' No support No Notes' Notes' See bug 176454.	Samsung Internet Android Full support 12.0

Legend

Full support: Full support
No support: No support
See implementation notes.': See implementation notes.