Slider in Apple store style

I know I would show some effort in this but I have no idea... I'm trying to make a slider like the one in the store section of Apple website.

enter image description here https://www.apple.com/store

The slider has to be aligned to the left side of the grid when the page is loaded and then it has to go full width when the user scrolls it. I can't find any solution. Can someone point me to the right direction?

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