Opacity

There are several ways to control the transparency of elements in CSS. The first is to use the opacity property, which allows you to set values between 0 (transparent) and 1 (opaque) on elements. This setting applies to the entire element, including the element's content. Using the rgba and hsla color definitions, you can add an alpha value (again, between 0 and 1) to control that color application's opacity. Using this method you can specify unique opacity values for any property that accepts color definitions.