Set the opacity of an element. The opacity will be applied to the element and all of its children.
- Enter a number in the range 0.0 to 1.0
- 0.0 is transparent
- 1.0 is opaque
- 0.5 is 50% translucent
- You cannot add a value greater than 1.0
- leave blank - Do not add a unit after the number
Find more information at https://developer.mozilla.org/en-US/docs/Web/CSS/opacity