errors in SlideshowPlugin/functional.css?ver=2.2.21

Hi,

My client came to me with a report that someone said her site doesn’t load in Safari. I can’t repllicate the problem–loads fine in Safari for me–but said I’d run some basic checks for invalid code. I ran it through the W3C validator, and got 5 errors, all in SlideshowPlugin/functional.css?ver=2.2.21 . And 2 warnings (besides the “unknown vendor extension” stuff).

I’d sure like to come back to her with “no errors found,” but it’s not true. Slideshow’s a great plugin, but a code-valid version would be very helpful!

https://wordpress.org/plugins/slideshow-jquery-image-gallery/