CSS backdrop-filter Property

div.transbox {
  background-color: rgba(255, 255, 255, 0.5);
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
}

Hello World!

Meaning

The backdrop-filter CSS property lets you apply graphical effects such as blurring or color shifting to the area behind an element.

Because it applies to everything behind the element, to see the effect you must make the element or its background at least partially transparent.

Default value:	none
Inherited:	No
Animatable:	No
Version:	CSS
JavaScript syntax:	`object.style.backdropFilter="none\|filter\|initial\|inherit\|revert\|revert-layer\|unset";`

backdrop-filter: none|filter|initial|inherit|revert|revert-layer|unset;

The numbers in the table specify the first browser version that fully supports the property.

The following table describes the values of this property.

Value	Description
none	No filter is applied to the backdrop.
filter	A space-separated list of filter-functions like: blur(): Blurs the image. brightness(): Makes the image brighter or darker. contrast(): Increases or decreases the image's contrast. drop-shadow(): Applies a drop shadow behind the image. grayscale(): Converts the image to grayscale. hue-rotate(): Changes the overall hue of the image. invert(): Inverts the colors of the image. opacity(): Makes the image transparent. saturate(): Super-saturates or desaturates the input image. sepia(): Converts the image to sepia.
initial	Sets this property to its default value.
inherit	If specified, the associated element takes the computed value of its parent element animation-delay property.
revert	Reverts the cascaded value of the property from its current value to the value the property
revert-layer	Rollback styles to the ones specified in previous cascade layers.
unset	Resets a property to its inherited value if the property naturally inherits from its parent, and to its initial value if not.

selectors {
  backdrop-filter: none;
}