Scroll through element 200vh then stick until end of page

Hi there,

I am trying to make my lottie animation sticky but only once you have scrolled through 2/3 of it. So it is around 300vh height and it should stick after 200vh. However, there is a section before it so it only starts from 100vh down the page. Hope that makes sense.

My preview link may help - the ball that moves is supposed to become a progress bar that scroll with you until the end of the page. The line should cover the left of the ‘electric transport’ section and then stay there for the rest of the page.

Thanks in advance!

Here is my site Read-Only: LINK