Image overlap first slide

I am having an odd problem where the second slide is overlapping on the bottom of the first slide by 100px right when the slide show loads, once the second slide animates in from the right all works fine, even when looping back to the first slide.

I looked in Chrome developer tools and it seems the second <div> slide is getting a top of 400px when the slides are 500px.

I am not sure why it’s subtracting 100px. Any advice would be much appreciated, even if it’s just pointing me where to look.

https://ww.wp.xz.cn/plugins/slideshow-jquery-image-gallery/