I would like to know that is there anyway to make changes in .css file using Jquery or javascript. I know, I can dynamically add css properties(or classes) to DOM Element but I
Not really.
There's some ActiveX stuff in IE that lets you modify things in the file system but aside from not being a recomended solution, they'd only work in IE anyway.
You can still modify the styles your page uses for selectors in your css files, but you won't actually be modifying the css file itself.