在没有向下推画布的情况下在画布上有元素-Javascript

So I have a simple javascript that bounces a ball up and down on a canvas that takes up the whole screen. I want to add simple value sliders in at the top of the screen. The problem is when I create them they position themselves on top of the canvas and push the canvas down. So basically There is now scroll bars that I don't want, and you can't see the whole ball animation and the sliders at the same time (without zooming out). How can I have these sliders without causing the need for scroll bars.So I have a simple javascript that bounces a ba