This will be problematic if we add another class to `<html>`. We could be careful when adding classes, but it does introduce another vector for unintended bugs.

```
$ node
> s = "redesign no-js"
'redesign no-js'
> s.replace(/\s?no-js\s?/, '');
'redesign'
> s2 = "redesign no-js another-class"
'redesign no-js another-class'
> s2.replace(/\s?no-js\s?/, '');
'redesignanother-class'
```