css to change gallery style on one page only

I'm looking for the answer to this too!

Did you figure it out?

I am also looking for the answer to this one.

I did for a friend recently. If you share site url, we can help easier.

The easiest way I've been able to achieve this is creating a gallery page for each gallery - in my example I had "Home Slideshow", "Weddings", and "Portraits". For Weddings and Portraits I wanted a grid style while I wanted the home gallery to be a Slideshow. 

I applied site wide styles to be the grid galleries and then put "Home Slideshow" under not linked and added an index page where I wanted the gallery, added a gallery block set to slideshow, and then added the below code to remove the padding and give it the full-width look. 

#home-slideshow .Index-page-content {
  padding-left: 0px !important;
  padding-right: 0px !important;
  padding-top: 0px !important;
  padding-bottom: 0px !important;
  max-width: 100%;
}

Hope this helps!