[Proposal] @media url

Hi,

I find the CSS Media Queries very usefull, but imho, I think that miss an
another very usefull particularity, moreover, many solutions based on
JavaScript exist around the net, trying to do that...

My idea is pretty simple :  to have a Media Query on the current url,
usable like the attribute value selector, same selection behavior, like :

```
@media url^="protocol://sub.domain.
tld/page"
```

By this feature, I think it has never been easier to merge all styles in one
file without having to use stratagems, sometimes very complex, to apply
styles to specific elements of a certain page & may reduce the JavaScript
dependency and class/id attributes especially used to resolve that. (best
ratio page content / page code, on each page)

What do you think about it? :)


Michaël Rouges - https://github.com/Lcfvs - @Lcfvs