ISHIMOTO MOBILE VERSION: gallery grid text HELP

Site URL: http://www.andreaariasart.com

Hi,

Im using the Ishimoto template for my artist website. On the mobile version, the only way to be able to see the text about an image in a grid gallery when you click on an image is tapping on a really really small barely visible gray circle on the bottom right corner of the cellphone. I was wondering if anyone could help me making it bigger and black? 

Thanks-

Andrea

PS know nothing about coding so need step by step instructions please!