Website horizontal scroll snap to dividers using css

My problem is i don't know how to snap dividers to lock the scroll on every page.. i found a code that can use css to make it work, but i. can't modify as i want. it doesn't seems working for me:(.. any answers or advices is very acpreciated!.. Thank youuu.

Here's my HTML & CSS code :

Code pen : https://codepen.io/faizjie9/pen/rNVqXYY

And here's my example what i was expected :

Code pen : https://codepen.io/faizjie9/pen/WNvaVpr