CSS Property - Background Color
Value: <color> | transparent
Applies to: all elements
Percentage values: N/A
This property sets the background color of an element. When validating your CSS documents with the W3C Validator setting the "background-color" without a "color" will produce a "warning".
The use of "transparent" as a "background-color" will also trigger a "warning" with the CSS Validation Service. You need to ensure that when setting colours that the base colours are set in the body, so providing a correct cascade of colouring for accessibility issues.
To Validate without warnings: