将画布设置为窗口宽度并在不使用javascript的情况下调整大小?

I am creating an image viewer with a canvas which will pop open in a new window. I would like the canvas to be the width of the window and 100px from the top and bottom. I would also like for it to resize without using javascript (let me handle the redrawing in javascript - I just want to see the canvas stay fixed to the edges of the window with the top and bottom spacing.) How can I do this? I tried the following but the right and bottom are ignored:I am creating an image viewer with a canvas whi