Slider is not transparent in IE

Hi,
First of all, Im not a developer. Im trying to build a website using this free theme https://www.web2feel.com/rolex/
But the slider is not transparent in IE. ??
I dont know what to do. I read a comments from wordpress forum and added this line background-color:transparent !important;
But the line made things worst. So I took it off.
here the website I am trying to build – https://www.pet1.mtest.com.au
I would really appreciate if someone could help me with any suggestion pls.
Thanks
Zia