Caching not working with rack::offline in rails 4

HI,
I am trying to add the offline access with my rails 4 application with
the reference of railscast (
#248 Offline Apps Part 2 - RailsCasts), but the problem
with rails 4 is its not caching the JS & CSS files. its seems like

CACHE MANIFEST
b84e022ceae173fbc8d0c0dff68b25e9109869d744f42f1cacebfa87b96865a7
404.html
422.html
500.html

NETWORK:
*
is there any way to do the caching js & css with rails 4

Got the solution and sovled, that was the issue with JS