load all html files in browser for offline website

I ' m looking for a trick for loading all my html files in my browser in once, so as to navigate in my website in offline mode.
(for exemple load all of these and navigate from index.html

index.html
data/page.html
data/page2.html
data/page3.html
data/page4.html
script.js
style.css

)
thank you for your precious help :) :)