Theoverscroll-behavior-blockCSS property sets the browser's behavior when the block direction boundary of a scrolling area is reached.

Seeoverscroll-behavior for a full explanation.

Syntax

/* 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: revert-layer;overscroll-behavior-block: unset;

Theoverscroll-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 (e.g., "bounce" effects) is observed inside the element where this value is set. However, noscroll chaining occurs on neighboring scrolling areas; the underlying elements will not scroll. Thecontain value disables native browser navigation, including the vertical pull-to-refresh gesture and horizontal swipe navigation.

none

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

Formal definition

Formal syntax

overscroll-behavior-block =
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 largeheight set on it so the page will scroll vertically. The inner box has a smallwidth (andheight) set on it so it sits comfortably inside the viewport, but its content is given a largeheight 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 setoverscroll-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,    transparent 0px,    transparent 19px,    rgb(0 0 0 / 50%) 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,    transparent 0px,    transparent 19px,    rgb(0 0 0 / 50%) 20px  );}p {  padding: 10px;  background-color: rgb(255 0 0 / 50%);  margin: 0;  width: 340px;  position: relative;  top: 10px;  left: 10px;}

Result

Specifications

Browser compatibility

See also

• overscroll-behavior
• overscroll-behavior-x
• overscroll-behavior-y
• overscroll-behavior-inline
• CSS overscroll behavior module