Hi Shrug,
thanks for your help, this is a logic approach indeed.
Here's a link to a quick fiddle (sorry but didn't get the way to link scrollTo plugin)
https://jsfiddle.net/cjgyav39/
ScrollTo is working nicely, now I need to do the same with scroll based on Y mouse wheel
as i have comented my code
Can you give me a good approach to do that ?
Thanks again
and cheers from belgium