I was facing the exact same problem today with missing css3 coloring on properties like transform, -webkit-transform and so on
i found this plugin called SUBLIME-CSS3 - installing this plugin will add the missing css3 coloring + add the missing dropdown propperties.
Installation of SUBLIME-CSS3 (with Package Control):
Ctrl+Shift+P → Package Control: Add Repository → [github.com/i-akhmadullin/Sublime-CSS3](https://github.com/i-akhmadullin/Sublime-CSS3)
Ctrl+Shift+P → Package Control: Install Package → Sublime-CSS3
(in .css file) View → Syntax → Open all with current extension as... → CSS3
Hope it helped you solve your problem