Sticky Side Navigation

Site URL: https://tulip-tiger-l3hf.squarespace.com/about-1

password: brineintopedro

Hi! I am trying to create the left side navigation to be sticky, so as you scrolls it you scrolls with you. However, every code I find requires a section ID. When I use the SS ID finder, that text navigation I'm trying to make sticky is a "block", not a section. How do I work around this? 

Add to Design > Custom CSS

@media screen and (min-width:768px) {
div#page-section-622282ce64093033e4b7a018 .span-12>.row>.span-3 {
    position: sticky;
    position: -webkit-sticky;
    top: 50px;
}
}