License for CSS and HTML

At the bottom of the [License file](https://github.com/google/material-design-lite/blob/mdl-1.x/LICENSE) it says:
```
All code in any directories or sub-directories that end with *.html or
*.css is licensed under the Creative Commons Attribution International
4.0 License, which full text can be found here:
https://creativecommons.org/licenses/by/4.0/legalcode.
```

However the CSS files have a Apache License header, for example [`material-design-lite/docs/_assets/customizer.css`](https://github.com/google/material-design-lite/blob/88872e672e41c56af0a78a35b34373b8c4a8c49d/docs/_assets/customizer.css) has the Apache license.

Does this mean the CSS file is under the Apache license or the CC Attribution License?