css property
`overscroll-behavior-block` CSS property
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.
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;
Values
This property is specified as one of the following keyword 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, no scroll chaining occurs on neighboring scrolling areas; the underlying elements will not scroll. The
containvalue disables native browser navigation, including the vertical pull-to-refresh gesture and horizontal swipe navigation.
- : Default scroll overflow behavior (e.g., “bounce” effects) is observed inside the element where this value is set. However, no scroll chaining occurs on neighboring scrolling areas; the underlying elements will not scroll. The
none- : No scroll chaining occurs to neighboring scrolling areas, and default scroll overflow behavior is prevented.
Formal definition
Formal syntax
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,
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;
}