Article update: 12th December 2012The article has been updated to cover the gradient syntax covered in the (at the time of writing) latest Image Values and Replaced Content Module Level 3 specification, dated June 12th 2012. IntroductionGradients are much-used on web sites: if you want to liven up pretty much any UI feature (buttons, panels, headers, etc.) you can use a gradient, although you shou