Quantum is a simple, flat theme for Atom based around the Tomorrow color scheme. Pair it with the Quantum Syntax Theme.
Originally, somewhere under all this new CSS, Quantum originated and was forked from neutron-ui by @brentd, which was forked from the Atom port of Spacegray. Oh, how nice open source software is.
Good catch. Let us know what about this package looks wrong to you, and we'll investigate right away.