hello-bars demo has doctype issues?

Reported via an email:

I would like to point out that I've just run the 'c2-demos/hello-bars' you published on your github page and the bar visualization (sizing) fails if you add a doctype declaration 

```
<!DOCTYPE html> 
```

or 

```
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
```

to the html file 'hello-bars/public/index.html'.
