To make your website available offline point your HTML pages to the manifest file by setting the manifest attribute on the html element in each of our pages:
<!doctype html>
<html manifest="/cache.manifest">
Note:-
Note
Each HTML page on your website must set the manifest attribute on the html element otherwise application might not be stored in the application cache! There should be only one cache.manifest file for the entire application and every HTML page of your web application needs <html manifest="/cache.manifest">.
