atom-csscomb 
Sort CSS properties with CSSComb.
Installation
$ apm install atom-csscomb
Usage
- Packages > CSSComb > Sort properties
- Context Menu > Sort properties
- Command Palette (⌘ + shift + P) > CSSComb: Comb
Configuration
To configure with .csscomb.json, just put it to workspace.
Preset config
Configure with presets (csscomb, zen, yandex).
Extend preset
Extend selected preset config with project config if exists.