How do I hide a page in my main navigation in Forte Template?

Hi,

I am having trouble hiding a page called "Beyond Surface" in an index titled "Portfolio" in my main navigation. I would like to use the banner image of that page, but not have it shown in the drop down menu under "Portfolio" in my main navigation. So, simply moving it to the 'not linked' section wont solve the issue. Please refer to my page: www.officede.co

@k_k Add to Home > Design > Custom CSS

.index-collection.folder .folder-parent .folder-child li:first-child {
   display: none !important;
}

Reference: https://beaverhero.com/squarespace-all-css/

Thank you very much @tuanphan! It worked!

@k_k Accept Answer If it worked. Thanks.

@tuanphan It only works for desktop version but not mobile. Is there additional css code that I need to add? Thanks

@k_k

#mobile-navigation .index-collection ul li.page-collection:first-child {
   display: none;
}

@tuanphan Thank you it works!!