Is is possible to scale inline SVG with CSS?

I want to use CSS styles to control the size of SVG designs. For example...

.svg { width:100%; }

When I embed an SVG image from a file it acts just like any other image and works fine:

<img src="image.svg" class="svg" />

But when I use inline SVG it DOESN't work:

<svg class="svg">...</svg>

The svg "box" will grow, but the contents stay the same.

Is there a way to do this?