css_color.vim plugin by Niklas Hofer is great, but lacks two important features:

• Highlighting multiple colors on the same line (not sure if anyone uses it though)
• rgb and rgba color notation for all those fancy CSS3 niceties

So here is my patch.

g:cssColorVimDoNotMessMyUpdatetime is used when updatetime value set by plugin (100ms) is interfering with your configuration.

let g:cssColorVimDoNotMessMyUpdatetime = 1

Major kudos to rainbow-mode.el, from which I borrowed some code, and to ConvertBase.vim plugin I used for base conversion.

I highly recommend using pathogen.vim plugin for all your plugin installations. It's so good, it should be illegal. God bless Tim Pope.