BassCSS is very different from Bootstrap or any other CSS framework. It's more like "classed inline styles", so you build your element styling like 'border border-blue blue bg-white p1 m1' (blue border, blue text on white background, 1 unit padding, 1 unit margin) e.g. you mix-and-match different CSS classes to style your elements.
So, I was thinking using React + BassCSS, and build the class string in my React components. Not sure if it makes sense, but at least it would probably be a bit more manageable and faster to develop than inline styles. Inline styles could be added on top of that of course.
If that's the case, I stand corrected. But the thing is, I still consider Basscss a solution from the "CSS world". React, IMO, takes it to the next level and combines inline styles with JS features (simple example: https://youtu.be/7YwmS0ny-58?t=58m38s - the scalable font can be done in pure CSS but I could imagine more complex use cases). Still, everybody picks the tools that are best suited for the problem and his/her preferences.
So, I was thinking using React + BassCSS, and build the class string in my React components. Not sure if it makes sense, but at least it would probably be a bit more manageable and faster to develop than inline styles. Inline styles could be added on top of that of course.