Need help with 2 images switching as you scroll

Hi there! I’m more or less trying to replicate this effect that you can see on Lattice website here, where as the user scrolls through the website, the spreadsheet image turns into the dashboard image.

Found some similar projects but none of them helped me with this specific use case so any help would be appreciated. Below is what I’ve got so far (but even that doesn’t work on mobile).

Many thanks!

Here is my public share link: LINK