hide one page from side index navigation

Site URL: https://cello-pug-263f.squarespace.com/

Is there any way to hide one title from the side index navigation? The site is one long scroll with a side index, per client request. However, I want to have some panels that wouldn't show up in the side navigation. Is there any way to do this? I'm working around it, but my life would be so much easier if I could split some of the content into separate panels/pages.

I'm using a template in the Brine family. If you want to take a look at the page, the password is EnCore1! 

Add to Home > Design > Custom CSS

/* hide side navigation */
/* tuan 5mi */
a.Index-nav-item[href="#aircraft-interiors"] .Index-nav-text {
    visibility: hidden;
}

Do simiar for other items, remember changing #aircraft-interiors

@tuanphan This is CRAZY helpful. Thank you!!!