Border won't just go?

Can you show me a live URL to your gallery? is this the border on the lightbox window that pops up?

Yeah the lightbox window that pops up, here’s a live url

Try

#fancybox-content {
    border: none !important;
}

Yaayy, it worked….. but, the border now appears only at the right of the image window.

This should fix it. It’s because the padding is calculated with Javascript, and so removing the border via CSS makes the lightbox incorrectly apply a width.

Paste this function into your child theme’s functions.php. I’ve tested this and it now correctly calculates the width
https://gist.github.com/sumobi/10444247