How can I make smooth transitions between webpages of the same website by sliding only part of the screen

In my webpage right now I have three buttons each filling a third of the page width and all the page height. i want to make it so if I click on the first button the second two slide off to the right and the first button remains on the screen, I've done a bit of research and come up with nothing. if you need more information let me know thanks in advance!