Weird lighbox close button icon

Hi, I use your plugin for a couple years, and I always wondered: why does lighbox close button looks like an arrow on my website? – https://ibb.co/LkQ1S5v

I looked at this image’s path in Dev Console, and it has to look like this: https://ibb.co/yQvgvq9

What could possibly change it? Thanks in advance for an answer!

The page I need help with: [log in to see the link]