Atom UI theme with vibrancy support. Vibrancy it's kinda buggy and only available on macOS. You can use a background image to imitate the effect on unsupported platforms (Windows and GNU/Linux).
Based on Simurai's starter template.
Fire up a Terminal and type:
apm install vibrance-ui
Or… within Atom's settings. After that, you'll be able to pick the theme from Atom's settings.
Good catch. Let us know what about this package looks wrong to you, and we'll investigate right away.