I'm writing an UI library for JavaScript. I wish to release my work under the MIT license. As part as my code I wish to provide a hand crafted theme based on the look and feel of the Mint Y family of themes.
https://github.com/linuxmint/mint-y-theme
The original source code of this theme is licensed under the GPL V3. But this apply I suppose to the source code. Is legal to use the same look and feel in my product under a more permissive license?