Possible to alter the resolution used for the web view?

I`m working on an idea where I want to include a display that displays the “Now playing” web view from my Arylic amp.

It seems like the default optimal display resolution is 1280x1024 then including the gradientbackround.

Is there a way to display only the “black” main part?

My idea is to use an Raspberry pi + display in kiosk mode showing the web content from the Arylic