i think a lot about the placement of the lights in each of the brother's huts a lot. it feels very purposeful.
i've always seen it as a sort of representation of their outlook on their life passions. mato sits directly in the light, someone who eagerly inherits and wishes to pass the teachings of the nail arts. sheo stands outside of it, exploring something else - someone who wishes to find something new to dedicate his life towards, and who didn't see that in the path laid out for him. oro sits idly outside of it without doing much else, as he does not seem to see himself as "proven" as a nail master, or perhaps just simply feels dissatisfied with it from his struggles and stubbornness with the practice.
i hesitate to say that this is specifically about the nail arts, for the simple fact that sheo's place changes after the nailsmith arrives:
sheo seems to have changed following his arrival. his artistry turns from something he's attempting to something he passes down to another, much in a similar way to mato.
all in all a really neat detail that gives a little more sense to their characters, i think :)
