Javascript to modify cargo collective template

I am working on a cargo collective template, and I need someone to help me create a script that will manipulate the content that the CMS outputs. Cargo does not allow you to modify the html that is output, beyond their basic options. However it does allow for css, html & javascript to be added. My goal is to take a page with multiple galleries displayed (see attachment) and make it behave like the interior pages of this site: [login to view URL] (ignoring splash page and main nav). I believe this can be done with javascript, what needs to happen is: 1. The h2(gallery title) tags need to be indexed to correspond with their respective galleries (featured image & thumb) 2. All but the first gallery are hidden 3. All h2 tags are displayed and turned into anchors that will reveal their respective gallery, and hide the other galleries. I will provide you with login info for a test site on cargo collective. I need this done as soon as possible. Thanks for your time and happy bidding.