[soldermont001]

I tried to overlay an SVG logo over a photo background (jpg). While it more or less worked after futzing, it was a responsive website and re-sizing the screen caused the SVG to not stay aligned with the background jpg. It doesn't appear to be possible with CSS. So I had to just drop SVG and use a jpg instead. Lame.

[Raphael]

You can set the size in CSS just as you can with any element.

[soldermont001]

Right, but I wanted it to fluidly resize in the WP twentyeleven theme, so setting it to a fixed size wouldn't work.