Unhiding logo/site title when scrolling down on homepage

Hi All,

So right now I have my site title hidden on the home page only using this code.

.homepage a#site-title {
    visibility: hidden;
}

But I wanted to see if it could become unhidden when scrolling down the page? 
And with a fade in effect? 
Also would be great for it to disappear again when reaching the top of the page but not totally necessary. 
Just want for the home page only. 

https://harp-cobalt-g6lj.squarespace.com/
Password: blueberry2

Let me know your thoughts! Much appreciated!! 

amazing thank you! 

Is there a way to have it fade in and out as it looks choppy when I scroll back to the top and the title reappears?

any insight on this would be amazing! Thank you!

Change to this code

.homepage header#header:not(.shrink) a#site-title {
    opacity: 0;
	transition: all 0.3s ease;
}
a#site-title {
	transition: all 0.3s ease;
}

amazing thank you!!