@dhiraj85,
Assuming that you newly created your AEM website AEM Project Archetype, and utilising default client library. clientlib-site, We can try to troubleshoot your situation. Please troubleshoot the problems below on the Author instance only.
1. Can view your client library under /apps/my-site/clientlibs/*, within http://localhost:4502/crx/de/index.jsp
2. Does your .content.xml setup properly and configured to be:
<?xml version="1.0" encoding="UTF-8"?>
<jcr:root xmlns:cq="http://www.day.com/jcr/cq/1.0" xmlns:jcr="http://www.jcp.org/jcr/1.0"
jcr:primaryType="cq:ClientLibraryFolder"
allowProxy="{Boolean}true"
categories="[${appId}.site]" />
3. Do you have a js.txt and css.txt file, configured properly?
If you don't know how to set up a client library, please take a look at these easy to follow tutorial videos:
- AEM(client library part 1) - https://youtu.be/nF_btgaUTIM
- AEM(client library part 2) - https://youtu.be/caJa4i35UPI
- AEM(client library part 3) - https://youtu.be/mFeieUsaMDY
4. If above step 1, 2 & 3 are validated, we can move on to step 5.
5. Validate the generated .css reference in your page. Go to your page that you are testing and open "view page source", and find the .css reference. Can you find it? Click and View the .css file, does your CSS exist in the code?
6. During development on the AEM Author instance, after a re-build and deploy of your project code, can you see your code changes in /apps/my-site/clientlibs/*? We are trying to troubleshoot the basics so that we can understand what the underlying problems are.
7. Once steps 1-6 have been validated, you can move to the more advanced topics that others have mentioned, like reviewing the cache and recompiling the JS and CSS.
If you are really stuck, I suggest you spin up a new Author Instance, then use your maven skills to set up a brand new AEM project, AEM Project Archetype. With the new AEM project, you can use this as a sandbox for you to learn how client libraries behave and how they are setup. After when the project is built, you can make adjustments to clientlib-site, and just study and observe the behaviours of how your changes are being added into AEM and the outcome of the page.
I hope this helps. Happy Learning AEM!