problem in css background color transparent

[rhodarose]

I have a navigation button and it has a color green line below the button i want that the line is become a tranparent so the the background of my webpage can see even though the line is on the top of the background..

[Beverleyh]

Need a link to the page so we can see what we're dealing with.

[inspirations unlimited]

I have a navigation button and it has a color green line below the button i want that the line is become a tranparent so the the background of my webpage can see even though the line is on the top of the background..

Yup. A live link will be great. Thanks