Hi Diler,
Thanks so much for reaching out!
I understand you're looking to remove the padding appearing around your slides. May I ask if the padding shows in both preview mode and when published to your LMS? If you're willing to provide a screenshot or screen recording of what you're seeing, that would be greatly appreciated! You can upload those here in this thread or privately in a support case where we'll delete them after troubleshooting.
I also wanted to highlight this article on calculating the dimensions of your published course as well as a similar discussion about editing the player options that may be helpful!