Just a quickie to pass on a little workaround for using RGBA values in CSS3, having it render fine in Safari and Firefox and rendering a solid in non compliant browsers.
Basically just input two 'background' values into the stylesheet.
padding: 0 0 10px;
background: rgba(0, 0, 0, .75);
The first is picked up by non CSS3 compliant browsers and the second by those that are compliant with CSS3.
Can't tell you how relieved and easy this was, I had been thinking about it for quite some time.
Hopefully it's of use to someone.
Example here. http://michaelclements.co.uk/