interactive mirror

how to make a mirror like this and make it interactive? I want it to expand to the front as transition to the next page. https://www.awwwards.com/sites/cartier-watches-and-wonders

Cartier Watches and Wonders - Awwwards SOTD

Discover six immersive universes meticulously crafted for Cartier Watches and Wonders. Step into each unique realm and discover an iconic watch model...