Showcase slider not centered

Hi,

I have created a Showcase gallery and slider and added the link to one of my pages, but because the theme I purchased from my designer used full-width images, and my gallery images are smaller, my slider is left-aligned. How do I move my sliders on my gallery pages to the center?

My designer is unable to assist at this point (I have already used all of my support requests :(. I’m new to WordPress. Can anyone help?

Here’s where one of my sliders lives: https://www.hayleyjophotography.com/newborn-2/

Thank you!
Hayley