creating a transparency in keynote?

[waterman315]

I watched a youtube video where the presenter created a new slide using a black background in keynote. Later in the video, he suggested using the slide inspector and change the opacity of the black background from 100% to 0%. I have keynote v8.1 and nowhere could I find the ability to change the opacity of the background color of the slide? Is there a step missing? HELP! creating a transparency for use in iMovie is really important to me. I am creating an online class and having that option is critical.

 

[Dave Braine]

Create a Keynote project with a white background. Then add a black rectangle that covers the whole slide. You'll be able to adjust the opacity of the rectangle.