I can't change the size of my video

I am building my website “H.stories” but I encounter a problem at the collection page “Events Template”

On the left hand side of the page I want to display a fixed video that will be different for each collection item. I have tried vimeo/youtube and mux.com but it never comes out the way I would like to. I want this video to be fixed at 100VH and width: 40%. The problem is that the video always appears cropped, we only see 60% of the height and then we cannot see the player bar at the bottom of the video and the play button is then not centered. Another issue I have is that right when I arrive on the page, the video starts small and 1 second after expands to fit the dimension I want.

Also, this happens to me on every website recently. Every time I place an image, even though I put 100% width it will suddenly disappear in the designer and also on the published site. Sometimes it will work on the published site but only on desktop but not mobile. It’s been happening quite frequently and I would like to know the solution for that.

Hope that it all makes sense :slightly_smiling_face:

Here is my site Read-Only: LINK
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