veinjs is a library that injects CSS into the document (it's a perfectly legal procedure). Rather than using inline styles, the CSS is being pushed into a dynamically generated stylesheet that's injected into the header.
This approach gives us a couple of benefits:
(if you're on a small screen device, it will turn red. If you're on a big screen device, resize your browser and see the injected media query in action). This is acheived by running the following code:
vein.inject([{'@media (max-width: 768px)': ['#friendly-cube']}], {'background-color': '#F00'});
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