CSS not compiling in server

Hello everyone,

I am using rails 3.2.8
In local my site working well with css file.
But In staging my css file not getting compiling but my js and images
compiling but not css.
and I am just importing css file in application.css

In my Capfile, i having following code,
load ‘deploy’
load ‘deploy/assets’

I don’t know why.
Any idea?

Please advise!