Video background not resizing with browser width

Greetings,

I created this simple landing page with video background, but on other screens and when reducing width of my browser, the sides of the video get cut off…a lot. (all on desktop >600px width)

What do I have to change so that the video resizes with the browser and on any desktop/laptop screen shows 100% of the video width, taking up 100% of browser width?

Thank you in advance for any help!

Rasmus
PS: I do not have a programming background and minimal experience, so for dummies would be great :slight_smile: