This property sets the opacity of an element as a whole, including its contents, rather than applying it to each descendant individually.
Values for "opacity"
|CSS3||a number between 0.0 and 1.0|
- 0 is fully transparent and 1 is fully opaque (solid). Any values outside the range 0.0 (fully transparent) to 1.0 (fully opaque) will be clamped to this range.
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