ISSUE IN DESCRIPTION BOX (NOT READABLE)

Greetings

Clicking the link https://www.sir-mar.com/products/#5/423 (valid for all other photos in “reusable section” on my website) and hovering “i” button to see photo description, description text cannot be read. I tried all transparency adjustments but no way to fix it. Any help please? Thank you